Programming style, uppercase

I heard that writing variable names in upper case is bad. Is there a real motivation or is just a convention?

>>11
No, no.
My post is formatted like int LeftArm, and indeed looks retarded. Traditionally (i.e. in C and every C-like after it), BactrianCase is used for enumerations, ALLCAPS and ALL_CAPS for macro definitions, and either dromedaryCase or underscores_as_spaces for general variables.

Imagine reading code as if you were reading prose. Capital letters for the beginning of each word are unnatural and ugly.
Clearly the winning method is underscores_as_spaces.