Why is it necessary to use time in UTC format?

To standardize and avoid confusion with time zones and daylight saving time. It allows for correct exchange of time data between systems in different geographical locations.

Advantages of using UTC:

• Unambiguity: A single standard of time, independent of local settings.
• Ease of calculations: Simplifies operations with date and time, as there is no need to consider time zone offsets.
• Global synchronization: Ideal for systems working with users in different regions (e.g., online games, financial platforms, distributed databases).
• Reliable storage: Reduces the risk of errors when saving and retrieving timestamps.

In JavaScript, Date objects support working with UTC:

// Create a Date object in the local time zone
const now = new Date();

// Get UTC time in milliseconds since Unix epoch
const utcMilliseconds = now.getTime();

// Create a Date object from UTC time in milliseconds
const dateFromUtc = new Date(utcMilliseconds);

// Get date components in UTC format
const utcFullYear = now.getUTCFullYear();
const utcMonth = now.getUTCMonth(); // months from 0 to 11
const utcDay = now.getUTCDate();
const utcHours = now.getUTCHours();
const utcMinutes = now.getUTCMinutes();
const utcSeconds = now.getUTCSeconds();

When displaying time to the user, UTC is usually converted to the user's local time.