It is a gmail account. Every time you are prompted to enter your google account, what do you enter? Yup, it was that simple.
You're completely incorrect. You see how this actually is confusing!
A 'Google Account' is just a login that allows you to use a Google product. You can sign up with your own email address if you like. Go and try it:
> You're completely incorrect. You see how this actually is confusing!
This is historically inaccurate. I have never signed up for a Google Account and yet I have one.
Before Google+ and Google Apps existed as concepts, people had GMail accounts. Then along came other Google Apps, and GMail accounts were upgraded to Google Accounts which could do more than just GMail.
Fast forward a few years, and Google+ comes along, and confused the hell out of this even further.
Google had products that required accounts way before Gmail came along. Adwords started in 2000 and I think Google Groups started in 2001. I'm pretty sure I personally remember having an account for Google Groups before Gmail even existed, but I could be wrong.
I'm also certain I had a blogger account with Google back in 2003 sometime and Gmail didn't come along until 2004 for an April Fools day joke I think.
Yep, but you can't move from Gmail back to your own email address any more.