Question about lipstick / lipgloss?

I always get my makeup professionally done and the woman always asks if I brought my own to apply? She always has lipstick but it wears off as the night goes along and I need to reapply. This is one area I know nothing about except its red and she does an amazing job apply it. What should I be shopping for to keep in my purse to apply as needed? I have no clue about brand or type. The only thing I can say is its a pain when it rubs off on your teeth.