What does the phrase 'you had me at hello' mean?

Question

i know it's from that moive, i've never seen it thoe but yeah what does it mean?

Answer 1

It means they liked them from the time they met them.

Answer 2

It's because Tom Cruise said hello and then he gave a huge speech to convince her of coming back to him. And at the end of that speech she said: you had me at hello. (meaning: I would have accepted coming back to you just because I saw you coming back and saying hello)

Answer 3

it means i already had a crush on u before u said a word

Answer 4

I fell in love even before we said Hello.

I believe this phrase came from the movie Jerry McGuire. It was a really cute movie..you might want to watch the movie to understands its meaning.