Mobile calendar: Sync the built-in calendar on popular mobile phones such as Android and iPhone with your Google Calendar or access your calendar from any device with a web browser.
Unbelievable offline support: The calendar app for Chrome lets you view your schedule and respond to invites, even when you don't have an internet connection. Your calendar and RSVPs will be synced the next time you connect to the internet.
Delegate and win: If someone else helps you manage your calendar, you can make this even easier by delegating access to that person. This allows another user to create events, respond to invites and manage your schedule.
Timezones don’t matter: Google Calendar makes it easy to work with people in other timezones. Features like timezone conversion makes sure your calendar time zone follows you when you travel and customizable working hours reminds your colleagues not to schedule meetings in the middle of the night.
Keep Outlook synched: If you use a desktop calendar application such as Microsoft Outlook, Apple iCal or Mozilla Sunbird, you can keep it in sync with Google Calendar automatically.
Reminders? Covered: Get custom reminders in your inbox or on your mobile phone with all the details about your upcoming meetings and events, right when you need them.
Schedule events in a breeze: Google Calendar makes it easy to schedule events and can automatically send invitations and track RSVPs through your email.
Hang out, anytime: Hangouts brings online video meetings right to your laptop, mobile phone or tablet. Meet face-to-face with up to 15 colleagues or clients, from anywhere in the world with just a click.
Jump in and hang out: Hangouts is integrated with Google's productivity apps to fit the way you work. It's easy to schedule a Hangout from your Calendar, or jump right in from your inbox. You can add a doc from Google Drive and work together in real time during the meeting.
Awesome time savings: Whether you're working with a global team or interviewing a job candidate, Hangouts lets you connect without spending time on travel or money on specialized hardware. It's the next best thing to sitting in the same room.
If your Google Calendar is not working for Chrome browser, but works fine with other browsers, try this fix:
Step one: Open a new incognito window (Ctrl+Shift+N) and try to log in to Calendar there.
Step two: Go to Chrome:// extensions and disable all extensions, then try using Calendar again in your normal window.
This should solve your issues. The problem is often caused by an extension interfering with Calendar. See the full discussion in the Google Forum.
Photo used under Creative Commons from Philip Chapman-Bell