Pogue's Basics: Capitals don't matter

Even today, 25 years into the Internet revolution, you’ll give someone your email address, and they’ll be like, “All lowercase?”

People. On the Internet, CAPITALS NEVER MATTER. This includes email addresses, Twitter and Facebook names, and Web addresses.

Occasionally, the part after the slash in a Web address is case-sensitive.

But for everything else, including email addresses: C.D.M. (capitals don’t matter).