create email account : can i have multiple gmail accounts ?
http://bit.ly/Create-Gmail-Account
Yes , You can create and setup as many google mail accounts as you want , if you have the right reasons .

let's say you have one gmail account for personal matters and you want to keep it private from others.

Simply create another gmail account for business usage ,so you can send emails to coworkers,
explore business related searches, and schedule business calendar .

and if you are a sport fan , you can create new gmail address especially to send emails to teammates,
search for sports equipment, your preferred team news & practice and game schedule.

also you can have a gmail account for educating purpose , as example you want to teach someone google mail tips;
and how to use gmail new sitting and futures, and you don't want him or her to see your private messages .

as conclusion you can have multiple gmail accounts like :

- personal gmail account . [email protected] .
- google mail for work and business . [email protected] .
- a sport gmail email account . [email protected] .
- another gmail account for educational purpose [email protected] .

Ways to prevent you from mixing accounts.

- theme : Choose different Gmail themes for each account to give your in-boxes a unique design.
- photo : Use different profile pictures for each of your accounts.
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you can use multiple sign-in to switch between accounts
you can not Using multiple accounts simultaneously / in same time ; but you need to switch between accounts .


Using multiple accounts simultaneously
After the Google Apps transition, you'll find that you can't sign into another Google Account in the same browser while you’re signed in to your Google Apps account. Here's why:

Google uses cookies to keep you signed in to your account.
The Google sign-in cookie only lets you sign in with one account at a time.
In the past, Google Apps accounts were cookied separately from Google Accounts, so you could sign in to both your Google Account and your Google Apps account in the same web browser.
Your Google Apps account has undergone a transition, and now functions more like a full Google Account. Your account uses the standard Google sign-in cookie, allowing you to sign in to only one account at a time.

Learn more about multiple sign-in.
Sign in to multiple accounts at once
If you have more than one Google Account, you can use multiple sign-in to switch between accounts without having to sign out and back in again. For example, if you have one Google Account for personal use and a different Google Account for business, you can easily switch between the two within the same browser (like Chrome or Firefox) using multiple sign-in.
Add your Google Accounts
Sign in to Google.
Click your profile photo or email address at the top-right corner of the page.
Click Add account from the drop-down menu.
Account information