Track your work hours in Google Calendar

Google Calendar is a free time-management web application offered by Google. Turn on Applets to add the most important information, right into your calendar, automatically — and get custom notifications about the events that matter the most to you.
Get more done with Google Tasks. Keep track of your daily tasks, organize multiple lists, and track important deadlines with Google Tasks. Tasks synchronizes across all your devices, so your lists and tasks go with you, wherever you are.