[Denny]

Just wondering, and though this has zero to do with peak oil, or energy, I know there many bright people out there who might know the answer.

Why do we use lower case for email addresses?

I often find it confusing, and error prone. (Is that an "l" or a 1. Letters with tails on them, like p and q's are often illegible when written on prelined forms. Unlike words, email addreses do not have the advantage of context to guide one if in doubt.

Just to try, I sent three e-mails using capitals for the address, (like DENNY@HOPSCOTCH.COM vs. denny@hopscotch.com). To my surprise, it works.

[buster]

Email addresses are case-blind. This is to prevent confusion between addresses that might otherwise be identical except for case.

If you want, you can alternate -- fAkE.AdDrEsS@fAkE.CoM -- and it would work, as would JohnSmith@provider.net. Caps just don't matter.

The reason people use all lower case is that it looks nicer than all upper case (Internet tradition that all-caps is the equivalent of SHOUTING.)