What Is a Digital Watch: History, Functions, and Advantages

Digital watches revolutionized timekeeping with their innovative display and electronic technology. Unlike analog watches with rotating hands, digital watches show time in numerical form on electronic screens. Since their introduction in the 1970s, they’ve evolved from simple timepieces to multifunctional devices with various features and capabilities, becoming popular for their accuracy, readability, and practicality.

What Is a Digital Watch?

A digital watch is a timepiece that displays time in numerical form using digits on an electronic display rather than through moving hands on a dial. While analog watches use hour, minute, and second hands on a watch face to indicate time, digital watches present the time using digits, typically shown on LCD (Liquid Crystal Display) or LED (Light Emitting Diode) screens. These watches represent a significant technological leap in timekeeping, offering precise accuracy and additional functionality beyond what traditional analog watches provide.

• Digital watches use electronic components powered by batteries to track and display time, with most models employing quartz crystal technology for timekeeping, the same technology found in many analog watches but with a different display method.
• The display technology in digital watches primarily uses LCD or LED screens. When fed time data from the computer chip within the watch’s movement, a digital display shows time in characters, and typically also displays the day of the week and date, with high-contrast designs for easy reading.
• Digital watches are restricted to quartz movement technology, unlike analog watches which can use either quartz or mechanical movements. This electronic foundation enables their precise timekeeping and additional functionality.
• Digital watches are known for their exceptional accuracy, typically keeping time with an error rate of less than one second per day thanks to their quartz crystal technology. This makes them significantly more accurate than mechanical watches.
• Most digital watches include practical features beyond basic timekeeping, such as multiple alarms, countdown timers, chronographs (stopwatches), multiple time zones, date and day displays, and some even include calculators, compasses, altimeters, and barometers.
• Digital watches are generally more affordable than their mechanical analog counterparts while offering greater functionality, making advanced timekeeping technology accessible to a wider audience.
• The straightforward numerical display of digital watches makes them extremely easy to read, eliminating the need to interpret the position of watch hands, which is particularly useful for quick time checks during activities.
• Digital watches typically have longer battery life than smartwatches, with some models running for years on a single battery, making them more convenient for everyday use without constant recharging.

Digital watches combine technology and practicality in a way that few other devices can match. Their clear numerical displays eliminate the learning curve associated with reading traditional clock faces, while their electronic components deliver reliable timekeeping with minimal maintenance requirements. Though they may lack the artistic craftsmanship of fine mechanical watches, they make up for it with precise functionality and versatility. From basic timepieces to feature-rich tools for specific activities, digital watches continue to serve as practical solutions for our timekeeping needs.

History of Digital Watches

Digital watches represent one of the most significant technological shifts in personal timekeeping, changing not just how we read time, but also how watches were manufactured, marketed, and used daily. The journey from exclusive luxury items to everyday accessories traces the rapid advancement of consumer electronics and changing design sensibilities across several decades.

• The first digital electronic wristwatch was a Pulsar LED prototype developed in 1970 through a collaboration between the Hamilton Watch Company and Electro/Data, founded by George H. Thiess. John Bergey, the head of Hamilton’s Pulsar division, was inspired by the futuristic digital clock that Hamilton created for Stanley Kubrick’s 1968 film “2001: A Space Odyssey.”
• On April 4, 1972, the first commercial digital watch, the Pulsar, was finally ready for public release. Made in an 18-carat gold case, it sold for $2,100 (equivalent to a small car at the time) and featured a red light-emitting diode (LED) display. It was marketed as being “as silent as space” with no ticking sound.
• The early LED watches were extremely expensive luxury items, seen on the wrists of celebrities and even featured in the James Bond film “Live and Let Die” (1973) where Roger Moore’s character used a Pulsar.
• Digital LED watches remained out of reach for average consumers until 1975, when Texas Instruments began mass-producing them in plastic cases, initially retailing for $20 and dropping to $10 by 1976. This price reduction led to Pulsar losing $6 million and eventually being sold to Seiko.
• The first LCD watch with a six-digit LCD was the 1973 Seiko 06LC, although various forms of early LCD watches with a four-digit display were marketed as early as 1972. The LCD technology was more power-efficient than LED, allowing for continuous display without needing to press a button.
• Throughout the late 1970s and 1980s, digital watches exploded in popularity as prices continued to fall and technology improved. Companies like Casio and Timex became major players in the digital watch market with affordable, feature-rich models.
• The 1980s saw the introduction of more advanced features in digital watches, including calculators, data storage, and even primitive games. Casio’s Databank series became iconic for its ability to store phone numbers and other information.
• In the 1990s and 2000s, specialized digital watches for sports and outdoor activities gained popularity, with brands like Suunto and Timex developing watches with altimeters, compasses, and weather forecasting capabilities.

The transformation from luxury item to mass-market accessory happened remarkably quickly in digital watch history, making them one of the first widely adopted personal electronic devices. Their evolution paved the way for today’s smartwatches and wearable technology while establishing a distinct category of timepieces that continues to thrive alongside both traditional watches and newer smart devices. The early digital watches now enjoy collector status, with vintage models from the 1970s and early 1980s fetching premium prices among enthusiasts fascinated by these pioneering electronic timepieces.

How Do Digital Watches Work?

Digital watches operate using sophisticated electronic systems that convert energy into precise time measurements. Understanding their internal mechanisms helps appreciate how these deceptively simple devices maintain such remarkable accuracy. From the vibrating quartz crystal to the visual display, each component plays a crucial role in delivering reliable timekeeping.

• At the heart of most digital watches is a quartz crystal oscillator that vibrates at a very high frequency when an electric current is applied to it. These vibrations create an electrical signal that drives the watch’s display and functions.
• A typical digital watch generates 32,768 vibrations per second, which allows it to keep track of time in tiny increments of 1/32,768 of a second. This high level of precision enables digital watches to maintain accuracy within a few seconds per year.
• The quartz crystal in digital watches utilizes a property called piezoelectricity – when electricity is applied to the crystal, it changes shape slightly and vibrates at an extremely consistent frequency.
• This vibration frequency is fed into a chain of electronic components called “flip-flops” that function as frequency dividers, effectively counting the vibrations and dividing the frequency by 2 repeatedly until reaching a 1-second pulse.
• A microchip inside the watch takes this one-pulse-per-second signal and counts them to keep track of seconds, minutes, hours, days, months, and even years in more advanced models.
• In watches with digital displays, the microchip repeatedly divides the oscillator frequency to drive the hours, minutes, and seconds segments on the screen. It sends signals to activate the appropriate segments on the LCD or LED display.
• Digital watches are powered by small batteries (typically button cells) that provide the electrical current needed to keep the quartz crystal vibrating and the display functioning. These batteries can last anywhere from 2-10 years depending on the watch model and features.
• Water-resistant digital watches use special seals and gaskets around the case, buttons, and display to prevent moisture from damaging the electronic components inside.

The beauty of digital watch technology lies in its ability to maintain accurate time using minimal power. The consistency of quartz crystal vibrations combined with precise electronic counting makes these watches remarkably reliable timekeepers. This elegant engineering solution has remained fundamentally unchanged for decades, proving the durability of the design while allowing for continuous refinement in display technology, power efficiency, and additional features. Even as smartwatches introduce more complex functionality, the core quartz timing mechanism remains the gold standard for accurate, low-power timekeeping.

Types of Digital Watches and Their Specialized Features

The digital watch market offers an impressive variety of styles and functionality to suit different needs and preferences. From simple time-telling devices to specialized equipment for specific activities, there’s a digital watch for virtually every purpose. This diversity reflects how manufacturers have adapted digital technology to meet specialized requirements while maintaining the fundamental benefits of digital timekeeping.

• Basic Digital Watches: These straightforward models focus on essential functions like time, date, alarm, and perhaps a simple stopwatch. Brands like Casio and Timex offer affordable basic digital watches that provide reliable timekeeping without complicated features.
• Sports/Fitness Watches: Designed for active users, these watches include features like lap timers, countdown functions, water resistance, and sometimes heart rate monitors. They’re typically more rugged with shock-resistant cases and secure straps for active use.
• Tactical/Military Watches: These rugged timepieces are built for extreme conditions, featuring reinforced cases, extended battery life, night visibility, and sometimes specialized functions like compasses, altimeters, and barometers. Brands like G-Shock, Suunto, and Luminox are popular in this category.
• Outdoor/Adventure Watches: Specialized for hiking, climbing, or wilderness exploration, these watches often include altimeters, barometers, compasses, GPS functionality, temperature sensors, and weather prediction features to assist with outdoor activities.
• Calculator Watches: Popular in the 1980s and experiencing a retro revival, these watches feature a small calculator keypad, allowing users to perform basic mathematics on the go. Casio’s Databank series is the most iconic example.
• Diving Watches: Digital diving watches offer features specific to underwater activities, including depth gauges, dive logs, extended water resistance (typically 200m or more), and specialized dive timers to track bottom time and decompression stops.
• Hybrid Digital-Analog Watches: These timepieces feature both traditional analog hands and a digital display, combining classic aesthetics with digital functionality. The digital portion often handles features like alarms, dates, and secondary time zones.
• Retro/Vintage-Style Digital Watches: Many manufacturers now offer modern recreations of classic digital watch designs from the 1970s and 1980s, featuring the nostalgic aesthetics of early digital watches but with improved modern components.

From simple everyday timepieces to specialized equipment for professionals, the diverse range of digital watches available today demonstrates how versatile this technology has become since its introduction over fifty years ago. This variety ensures that consumers can find digital watches tailored to their specific needs, whether they’re looking for basic functionality, specialized tools for particular activities, or simply a style statement that reflects their personal taste or nostalgia for a particular era of design.

Modern Digital Watch Functions

Today’s digital watches pack an impressive array of features into their compact cases, offering functionality that goes far beyond simple timekeeping. Modern models combine traditional watch capabilities with advanced technology to create versatile wrist-worn tools. These features have evolved significantly over time, with manufacturers constantly innovating to add value and utility to their timepieces.

• Time and Date Functions: Beyond basic time display, modern digital watches often show the full date, day of the week, month, and year, with automatic calendar functions that account for varying month lengths and leap years.
• Multiple Alarms and Reminders: Unlike analog watches that may offer a single alarm function, digital watches typically provide multiple daily or weekly alarm settings with various sound options and snooze capabilities.
• Chronograph/Stopwatch: Digital watches excel at timing events, with stopwatch functions offering precision to 1/100th of a second, split lap timing, and the ability to store multiple recorded times in memory.
• Countdown Timers: Useful for cooking, exercise intervals, or any timed activity, these features allow users to set specific durations and receive alerts when time expires.
• Multiple Time Zones: World time functions or dual/triple time displays make digital watches ideal for travelers or those who work with people in different time zones.
• Illumination: Most modern digital watches feature backlighting systems for visibility in low-light conditions, ranging from basic LED illumination to electroluminescent panels that light the entire display evenly.
• Water Resistance: Many digital watches offer substantial water resistance, from splash protection to full diving capabilities, with specialized diving models rated for underwater use at significant depths.
• Health and Fitness Features: Some advanced digital watches include step counters, calorie tracking, exercise timers, and even basic heart rate monitoring without crossing into full smartwatch territory.
• Environmental Sensors: Higher-end outdoor digital watches may include altimeters, barometers, thermometers, compasses, and atmospheric pressure sensors to assist with weather prediction and navigation.
• Data Storage: Certain digital watches allow users to store information such as phone numbers, appointments, or passwords, particularly useful when a smartphone isn’t readily accessible.

These diverse features make modern digital watches versatile tools for everyday life, sports, outdoor activities, and professional use, all while maintaining the simplicity and reliability that distinguish them from more complex smartwatches. The continued innovation in this space demonstrates that manufacturers recognize the ongoing demand for dedicated timekeeping devices that operate independently from smartphones and offer specialized functionality with exceptional battery life. Even as smartwatches gain popularity, traditional digital watches maintain their relevance through these practical features combined with unmatched reliability.

Benefits of Wearing a Digital Watch

Digital watches offer numerous benefits over their analog counterparts, making them popular choices for many watch wearers. Their unique combination of technology, functionality, and convenience provides distinct advantages for various situations and users. These benefits have helped digital watches maintain their relevance even as smartwatches have entered the market with more advanced connectivity features.

• Superior Accuracy: Digital watches offer exceptional precision and accuracy, often gaining or losing only a minute or two per year thanks to their quartz crystal technology. This makes them significantly more accurate than traditional mechanical watches.
• Readability: The numerical display of digital watches makes time-reading instantaneous and unambiguous, eliminating the need to interpret the position of watch hands. This is particularly valuable in situations requiring quick time checks.
• Enhanced Functionality: Digital watches pack multiple useful features into a single device, offering capabilities like alarms, timers, calendars, and specialized functions that would be impossible or prohibitively expensive in mechanical watches.
• Durability: Many digital watches are designed with robust cases, shock resistance, and water resistance, making them highly durable and suitable for active lifestyles, sports, and harsh environments.
• Affordability: Digital watches are relatively cheaper than analog watches with similar functionality, making advanced timekeeping technology accessible to a wider audience. Even high-end digital watches are typically less expensive than luxury mechanical timepieces.
• Low Maintenance: Digital watches require minimal upkeep beyond occasional battery changes (often only needed every few years) and basic cleaning, unlike mechanical watches that demand regular professional servicing.
• Lightweight Comfort: The electronic components in digital watches typically weigh less than mechanical movements, resulting in lighter timepieces that can be more comfortable for all-day wear.
• Precision Timing: The ability to measure time to 1/100th of a second makes digital watches invaluable for sports timing, scientific applications, and any situation requiring precise time measurements.
• Adaptability: Many digital watches offer customizable features like adjustable alarms, multiple display formats, and user-programmable functions that can be tailored to individual preferences.
• Battery Efficiency: Modern digital watches utilize low-power electronic components that enable years of operation on a single battery, providing reliable timekeeping without frequent battery replacements.

These advantages make digital watches practical choices for everyday wear, specialized activities, and professional applications where reliability, functionality, and precision are paramount. While they may lack the heritage and craftsmanship appeal of mechanical watches or the connectivity of smartwatches, digital watches occupy a sweet spot that balances functionality, reliability, and ease of use. Their continued popularity demonstrates that these practical benefits remain compelling for many watch wearers seeking dependable timekeeping without complexity.

Choosing Between Digital and Analog Watches

The comparison between digital and analog watches highlights distinct differences in design, functionality, and user experience. Understanding these differences can help you determine which type best suits your needs and preferences. Both styles have passionate advocates and specific scenarios where they excel, making the choice highly personal based on individual priorities.

• Display Style: Analog watches use traditional hands and hour markers on a dial, providing a classic, intuitive way to tell time. Digital watches display time numerically, offering immediate readability without interpretation.
• Precision and Accuracy: Digital watches are incredibly accurate, often down to the second, powered by quartz movements or other electronic mechanisms that ensure precise timekeeping without manual adjustments. While quartz analog watches can be similarly accurate, mechanical analog watches typically lose several seconds per day.
• Movement Types: A vital difference between digital and analog watches is their timekeeping mechanism. Digital watches exclusively use quartz technology, while analog watches can use either quartz or mechanical movements.
• Functionality and Features: One of the biggest advantages of digital watches is their array of features. Many include alarms, timers, stopwatches, and even more advanced capabilities like GPS tracking and fitness monitoring. Analog watches with similar features typically cost significantly more.
• Aesthetics: Analog watches are valued for their traditional and classic appearance, capturing the essence of watchmaking craftsmanship. Digital watches tend to have a more modern, utilitarian look, which appeals to different style preferences.
• Battery Life: Digital watches generally have longer battery life than smartwatches but may require more frequent battery changes than simple analog quartz watches due to their additional functions and displays.
• Durability and Practicality: Digital watches are often designed with durability in mind. Many models are shock-resistant, water-resistant, and built to withstand harsh conditions, making them ideal for outdoor activities and work environments.
• Affordability: While there are high-end digital watches, many digital models are relatively affordable compared to luxury analog watches. Brands like Casio and Timex offer durable and functional digital watches at accessible prices.
• Readability in Different Conditions: Digital displays can be easier to read in low light when equipped with backlighting, while analog watches may require luminous hands and markers. However, some analog displays can be easier to read in bright sunlight compared to certain digital screens.

The choice between digital and analog watches ultimately depends on your personal style, functional needs, and the contexts in which you’ll wear your timepiece. Many enthusiasts choose to own both types for different occasions and purposes. Analog watches often serve formal and dress occasions with their classic aesthetics, while digital watches excel in sports, outdoor activities, and situations where specific timing functions are needed. The good news is that with the wide variety of watches available today, there’s no need to limit yourself to just one type.

How to Choose the Perfect Digital Watch

Selecting the right digital watch involves considering various factors to ensure it meets your needs, lifestyle, and preferences. This guide will help you navigate the options and find the perfect digital timepiece for your wrist. With countless models on the market ranging from basic timekeepers to feature-packed tools, taking time to evaluate your specific requirements will lead to a more satisfying purchase.

• Intended Use: Determine your primary purpose for the watch. Do you need it for everyday wear, sports activities, outdoor adventures, professional use, or special occasions? This will narrow down the features and durability requirements.
• Essential Features: Make a list of must-have functions based on your needs. Consider whether you require alarms, stopwatch capabilities, multiple time zones, water resistance, or specialized features like altimeters or heart rate monitoring.
• Display Readability: Examine the display type and clarity. Look for appropriate digit size, contrast, and backlighting options that suit your vision needs and typical usage environments (indoor, outdoor, low-light conditions).
• Battery Life: Consider how long the battery lasts and how easy it is to replace. If you dislike frequent maintenance, look for models with extended battery life or solar-powered options that recharge with exposure to light.
• Durability Factors: Assess the watch’s construction, including case material, crystal type, and water resistance rating. For active lifestyles, shock-resistant models with mineral or sapphire crystals and higher water resistance are recommended.
• Comfort and Fit: Check the watch dimensions, weight, and strap options. Digital watches come in various sizes and weights, and the band material (rubber, resin, nylon, metal) affects both comfort and style.
• Brand Reputation: Research reliable brands known for digital watches like Casio, Timex, Suunto, and Garmin. Established manufacturers typically offer better quality, warranty support, and replacement parts availability.
• Price Range: Set a budget that aligns with your expectations. Digital watches range from under $20 for basic models to several hundred dollars for advanced feature-packed versions. Determine what features justify higher costs for your needs.
• Style and Aesthetics: Consider the watch’s appearance and how it fits with your personal style and wardrobe. Digital watches now come in various designs from utilitarian to fashion-forward.
• User Interface: If possible, test how easy it is to operate the watch’s functions. Some digital watches have intuitive button layouts and menu systems, while others might be more complicated to navigate.

By carefully evaluating these factors, you can find a digital watch that delivers the functionality you need with the comfort and style you prefer, ensuring your timepiece becomes a useful and satisfying daily companion. Remember that the best digital watch isn’t necessarily the most expensive or feature-rich option, but rather the one that aligns most closely with your specific needs and preferences. Taking time to research and compare different models will lead to a more informed decision and greater satisfaction with your purchase.

How to Clean and Maintain Digital Watch

Proper maintenance of your digital watch ensures its longevity, accuracy, and appearance. Following these care guidelines will help keep your timepiece functioning optimally for years to come. While digital watches generally require less maintenance than mechanical timepieces, they still benefit from regular attention to preserve their functionality and aesthetics.

• Battery Management: Monitor your watch for signs of battery depletion, such as dimming display or decreased functionality. Have batteries replaced promptly by a professional or yourself (if comfortable) using the proper tools to avoid damage to the electronic components.
• Water Resistance Maintenance: Even water-resistant watches require proper care. Rinse with fresh water after exposure to saltwater or chlorine, ensure the crown or buttons are fully pressed/sealed before water exposure, and have water resistance tested annually if you regularly use the watch for swimming or diving.
• Cleaning Practices: Clean your digital watch regularly with a soft, slightly damp cloth to remove dirt, sweat, and oils. For stubborn grime, use mild soap and water on water-resistant models, avoiding harsh chemicals that can damage the case or crystal.
• Button Care: Operate buttons gently to prevent damage to internal mechanisms. If buttons become sticky or unresponsive, have them professionally cleaned rather than applying force that could damage the seals or internal components.
• Temperature Considerations: Avoid exposing your digital watch to extreme temperatures, as high heat can damage the battery and electronic components, while extreme cold may temporarily affect the display or battery performance.
• Impact Protection: Though many digital watches are designed to be shock-resistant, excessive impacts can still damage internal components. Remove your watch during activities that might expose it to severe shocks or vibrations.
• Storage Methods: When not wearing your digital watch for extended periods, store it in a cool, dry place away from direct sunlight. Consider removing the battery if storage will exceed several months to prevent potential leakage and damage.
• Display Preservation: Be mindful of the watch crystal/display. While digital watch displays are typically durable, they can still be scratched or cracked. Consider models with mineral or sapphire crystal for better scratch resistance if this is a concern.
• Strap Maintenance: Clean rubber, silicone, or resin straps regularly as they can trap skin oils and dirt. For fabric straps, allow them to dry completely if they get wet to prevent odors and deterioration. Replace worn straps promptly to avoid losing the watch.
• Professional Servicing: Have your digital watch checked by a professional every 3-5 years, especially for high-end models or those with advanced features like environmental sensors that may need recalibration.

With proper care and maintenance, a quality digital watch can remain a reliable timekeeping companion for many years, often outlasting multiple battery changes while maintaining its functionality and appearance. Unlike their mechanical counterparts that require regular servicing of complex moving parts, digital watches primarily need attention to their power source, water resistance seals, and external components. This relatively low maintenance requirement is one of the many advantages that make digital watches practical choices for everyday wear.

The Future of Digital Watches in a Smartwatch World

Digital watches continue to evolve, incorporating new technologies while maintaining their core appeal of simplicity and reliability. Current trends and emerging innovations suggest an exciting future for these timepieces in an increasingly connected world. Even as smartwatches gain popularity, traditional digital watches are finding new niches and adapting to changing consumer preferences.

• Integration with Smartwatch Features: Many digital watch manufacturers are incorporating selected smart features into traditional digital designs, creating hybrids that offer connectivity benefits without sacrificing battery life or simplicity.
• Improved Power Solutions: Advancements in solar technology, kinetic energy harvesting, and battery efficiency are extending the operational life of digital watches, with some models now running indefinitely with minimal light exposure.
• Enhanced Display Technologies: New display types with better contrast, wider viewing angles, and improved power efficiency are making digital watches more readable in all lighting conditions while conserving battery power.
• Health and Wellness Monitoring: Some digital watches now include basic health tracking features like step counting and heart rate monitoring, bridging the gap between traditional digital watches and full smartwatches.
• Environmental Sustainability: Manufacturers are increasingly focusing on eco-friendly materials, solar power, and sustainable production methods to reduce the environmental footprint of digital watches.
• Advanced Sensors: Improvements in miniaturization are allowing more sophisticated environmental sensors to be incorporated into digital watches, enhancing their utility for outdoor activities and specialized professions.
• Customizable Interfaces: Some newer digital watches allow users to customize display information, rearrange functions, and prioritize features to create a more personalized user experience.
• Improved Durability: Ongoing advancements in materials science are creating more resilient cases, crystals, and components that extend watch longevity and performance in extreme conditions.
• Targeted Specialization: Rather than competing directly with smartwatches, many digital watch makers are focusing on specialized niches like diving, military applications, or extreme sports where reliability and specific functions are prioritized over connectivity.
• Retro Revival: The nostalgia for classic digital watch designs from the 1970s and 80s continues to fuel interest in both vintage models and modern reinterpretations of iconic designs, suggesting a sustainable collector market.

While smartwatches continue to gain popularity, traditional digital watches maintain their relevance through reliability, simplicity, durability, and specialized functionality. The future of digital watches likely lies in finding the optimal balance between technological advancement and the core values that have made them enduring timepieces for over five decades. By carving out distinct niches and embracing strategic innovation without compromising fundamental benefits, digital watches will continue to find their place on wrists around the world for years to come.

Conclusion

Digital watches have come a remarkable distance since their introduction in the early 1970s, transforming from expensive novelties to essential timekeeping tools for millions around the world. Their journey represents one of the most successful consumer electronic innovations, blending practical functionality with accessible technology in a format that remains relevant despite numerous technological advances.

The enduring appeal of digital watches lies in their perfect balance of simplicity and utility. They provide accurate timekeeping and useful features without the complexity, constant maintenance, or daily charging requirements of more advanced wearable technology. For many users, this combination of reliability, longevity, and straightforward operation represents the ideal timepiece for daily wear or specialized activities.

Whether you’re an outdoor enthusiast needing reliable tools in remote locations, an athlete tracking performance with precision, a professional requiring dependable timekeeping in challenging environments, or simply someone who appreciates practical design, digital watches continue to offer compelling benefits in our increasingly connected world. As technology continues to evolve, digital watches adapt and improve while maintaining their core identity as trustworthy companions for keeping time in an ever-changing world.