I cannot remember where I got this or if I put it together at some point. I know it might be helpful to someone, so without taking credit for it, I will share it in the name of helping others.
Based on MySQL version 5.0.
1 Storage will be # of characters or bytes, plus byte(s) to record length.
2 These String data types are NOT case sensitive, unless given the “binary” attribute or have a case-sensitive CHARACTER SET collation.
“E” is an abbreviation for “exponent”. E18 means move the decimal over 18 places (search “scientific notation”).