Used when you want to say the same thing in return to someone, but you can't be arsed to type the full thing. Means 'same here' pretty much.

when you're talking to someone, and they are thinking/doing the same thing.

basically means "you said it" in Italian.
(past participle of dire which means to say)

a term of complete agreement.

when written, " " is the ditto sign, indicating to repeat what precedes it.

done it two times over
(same or i agree)

What a male says to a female* in response to "I love you".

(*See annoying whore)

a worksheet, paper, or handout.