my bad ? what ?

[Roger]

> That's right, my bad. ^^
>
>
>
> help
>
>> In order for anybody on this list to help you we have to know what kind
>> of help you need or want.  What is your difficulty?
>>
I do not mean to flame but simply do not understand the " my bad" 
comment we  see with increasing frequency on list.
"my bad" actually means nothing at all, why would anyone do, posses, 
have or own a bad?
Is it shorthand for my badger or my badge?
Would it not be in keeping to say something like, "Oops", or "my 
mistake", or "Yes I should have.." or just simply fix the problem?