Contemporary piano involves learning to play from a chord chart or lead sheet - the lyrics or melody of a song with chords written above it. Students may play songs in the genres of pop / rock / jazz / worship, and they develop the skills to create their part based on the chords. When you go to a pop/rock etc concert, this is how the band members are playing the songs.
It requires an understanding not just of basic chords, but chord extensions like 7ths, 9ths, sus4 and sus2, altered chords, chord substitutions and more. If you want to play jazz, there's a whole extra layer of complexity on top of that.
Students also need to develop skills in maintaining a tempo, creating interesting and appropriate rhythms, improvisation, and how to create interest and variation within a song. It's a lot to get your head around initially, as there are more choices to be made than in playing a scored part, but there's a huge amount of fun to be had once you've developed some basic contemporary skills.