Gmail does not recognized (.) dot as a character within user-names. You can add or remove (.) dots from your Gmail username without actually changing the email address, i.e. you can create as many aliases of your email address and all will point to the primary address only.
For eg. your email address is email@example.com
#Adding a dot anywhere in the username wont change the email address.
So for example:
A mail sent to firstname.lastname@example.org or email@example.com will get delivered to the firstname.lastname@example.org.
You can even create aliases with such high alterations:
email@example.com = firstname.lastname@example.org
email@example.com = USERNAME@gmail.com
firstname.lastname@example.org = User.Name@gmail.com
All these addresses will behave similarly. You can verify this by signing into Gmail with your username by adding or removing a dot from it. You’ll still go to your account.
#You can even create aliases by adding some random text after you username preceded by a + sign. For eg.
The mail sent to above email address will get redirected to the email@example.com.
These limitations of Gmail could be brought into various uses:
1. Create multiple accounts on twitter using a single email address. (for eg. personal a/c and business a/c)
2. If you need to enter your email address at any untrustworthy place you could enter some alias instead of your original address. So you can block it at some later stage if required.
for example –
While signing up to any newsletter you could enter – firstname.lastname@example.org
So in case of any spamming, it will be easy for you to identify who distributed or sold your email id to third-party and you will be able to easily block it.
Note: Google Apps does recognize dots. If you’d like to have a dot in your username, please ask your domain administrator to add your preferred username as a nickname.