This might be really obvious to some of you, but it struck me recently that not everyone knows what words gotta replaces.
There are some who believe that gotta replaces "got to." But, the truth is that gotta stands for "have got to."
"I gotta go to the movies." IS EQUIVALENT TO "I have got to go to the movies." AND NOT EQUIVALENT TO "I got to go to the movies," which means something completely different.
"Got To" means "was able to," whereas "Have/Has Got To" holds a meaning much closer to "must."
A pretty mundane observation, really... but it was a real source of confusion the other day when I was chatting with a friend online. Just wanted to straighten everyone out.