Practically all of Google's services can be accessed via HTTPS, which makes for a totally secure connection across the Internet--the same kind of connection online banks use. Just add an "S" to the http:// part of the address to make https://. For example, to view the Microsoft Word file mentioned above over a secure connection, you could type the following:
Gmail can be configured to use HTTPS always by clicking the Settings link at the top right, and then selecting Always use HTTPS under the Browser Connection heading that appears.
4. Avoid Account Hijacking
To ensure that nobody but you ever accesses your Google account, you can have Google phone you with a confirmation code or send a SMS to your cell phone, every time you login. That way, even if somebody steals or second guesses your password, there's simply no way they can access your account.
This security is known as a two-stage verification procedure, which you can set up here. Note that this service is still being rolled out and might not yet be available to you. Keep checking back, however, because the intention is for it to be available to all Google users.
A drawback (or benefit) of the new security is that you might need to add new, specific passwords for certain Google services, such as mobile Gmail, desktop Picasa, or AdWords Editor. This is because these services don't yet work with the two-step verification process. Signing up using the link above will walk you through what's required.
5. Use Two Different E-mail Addresses
You might already know about Gmail aliases, which is to say, using periods or plus symbols to extend your standard Gmail address so you can filter for spam.
What you might not know is that you can use @google-mail.com as well as @gmail.com. In other words, if you normally use email@example.com for your e-mail, then you can also use firstname.lastname@example.org , and the message will still reach you. You could use @google-mail.com when signing up to newsletters, for example, and create a filter rule within Gmail to sort any messages sent to that address into a spam folder.
The @google-mail.com address came about because of trademark issues in Europe, where Gmail was already being used by rival services.
6. See Who Last Accessed Your Account
Worried somebody's been snooping on your Gmail account? By clicking the Details link at the very bottom of the Gmail page, you can view when, where and how your Gmail account was last accessed. The last 10 logins are listed.