A barre chords is a guitar chord in which the first (or another finger) holds down two or more adjacent strings (i.e. it “bars” several notes). Here are some examples of a barre chord diagram:
Want to learn more about barre chords? Check out this article on how to play all major and minor chords with just four basic chord shapes.
If you want to avoid playing barre chords, you could use a capo. Super handy!