Learn Korean: Thank you

I will try to regularly post basic but helpful Korean expressions. Hope this helps :)
Today's Expression is 'Thank you'

Expression / Pronunciation / When to use

고맙습니다 / Go Mop Sum kNee Da / To the person you don't know, or older than you, or higher in rank in the organization
감사합니다 / Gam(like Arm sound but without R) Sa(Ah sound) Ham kNee Da / Same as above
고마워 / Go Ma(Ah sound) Wo / To close people, especially to the same age or younger than you. Sometimes can be used to the older people if very close and agreed.

고맙습니다!