To open the address book, also known as contacts, simply open Gmail in the web browser, click the small downward pointing arrow next to the Gmail logo in the top left corner (above the Compose button), and select Contacts. The keyboard shortcut to open contacts is G followed by C.
From the contacts menu, users can add new contacts or organize and edit existing contacts. Within contacts, users can organize people into different groups such as family, co-workers and friends. There is also the option to import contacts from an existing contacts list for a different email account. Gmail even saves anyone users have had an email conversation with as Other Contacts, even if the user never saved them as a contact.