Today I overheard someone in the office ask on the telephone for someone else’s email address. “Is that all lowercase?” he enquired, using one of the most pointless phrases of the modern age. If we added up all the instances of its utterance over the years, I wonder how much time would have been wasted. Hours, days, months, or even years?

Everything after the @ symbol is not case sensitive and never has been. So, @somedomain.com is exactly the same as @SOMEDOMAIN.COM. However, in theory the mailbox name (everything before the @) is case sensitive but the potential for confusion means that very few, if any, email providers use case sensitivity for the mailbox name. If they did, the two following addresses would be different:

john.smith@somedomain.com
John.Smith@somedomain.com

It doesn’t take much to imagine the ensuing confusion if two different John Smiths each had one of these addresses. If john.smith’s granny sent an email to John.Smith, then the intended recipient would never receive it. Also consider that john.Smith and John.smith (or any other combination of lower and upper case letters) would also be unique addresses. As people make mistakes all the time when typing, it’s far easier to make email addresses non-case sensitive.

When you think about it, it makes sense. Now, if only I could make my colleagues think…