What is a Google Account?

Generally, searches can be done on Google from the Google home page without logging in.
However, Google also provides other services that require logging in with a login name and a password.

A Google Account is required to gain to access to some capabilities of properties and services that Google provides.

The login name must be a valid e-mail address that actually exists. It could be on any domain, not necessarily on gmail.com, so you can get a Google Account with a hotmail email address, a yahoo email address, your ISP email address, or with your company email address. However, if you use any of these addresses, Google sends an email to the address asking you to verify that in fact you have applied for a Google Account with that login name. If that email address is not yours, or if it does not exist, then you will not be able to verify the address, and so you will not be able to complete creating your Google Account.

The first time you try to log in to any property or service requiring a login for the particular Google Account, you need to accept the Terms and Conditions of Service before you can proceed. Some properties or services require you to log in before you can use any part of it. For instance, gmail provides email service, and a gmail email address is required to log in. Without a gmail email address you may not use gmail services. As an aside, I have found that associating a gmail email address with an existing Google Account with a non gmail address causes the gmail email address to become the primary login name (and identifier) for the Google Account.

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