Does it help being an authorized user of a credit card build credit history?

I want my wife to build her credit history, will it help her if I name her an authorized user of my credit card? Will the credit card company ask me for her data? The reason I ask this is because I noticed that when giving her an additional credit card the credit card company won't ask her data? So which is best, giving her an additional credit card or making her an authorized user? Thanks for the help, I'm from another country and I'm trying to build credit history.