What is the difference between a chord and a triad on a piano?

I do not understand the difference between a chord and a triad on a piano. Are they the same thing or do they have differences? (i.e. Cmaj. chord v.s. Cmaj. triad)

I do not understand the difference between a chord and a triad on a piano. Are they the same thing or do they have differences? (i.e. Cmaj. chord v.s. Cmaj. triad)