Everyone has different interpretations...

But I'd say:
1st - Kissing/Making Out
2nd - Feeling each other up
3rd - Oral activities
Home - Actual sex.

1st base - eye contact
2nd base - smiling
3rd base - raise a barn together

What? I'm Amish!

in my time
1st was kissing
2nd was under the shirt
3rd was in the pants
Home run was full on sex...

*Trying to word this for all viewers should a minor happen across this*

First base is kissing/fondling.
Second base is oral action.
Third base is full-on *cough* action.

There's slightly different interpretations that of course will differ from mine, but that's how I've learned it.

Have fun!

shit nman i think it should be first second fourth and then home or we could just say

first is kiddin makin out

second feelin up thah boobies

third fondling of the genetailia

hone oral shit

and then ima juss say once u get back to the doug out ur what ever thats when u have sex


but it aint like that

its juss 123 home with home beeing sex so its kinda confusing cuz really depending on who the definition may change but yah u get what ise sayin bruthah

hope that helped any

In regards to what? Making out as some say? When you are close to a home run.. put it that way.