Among many species, applause is a sign of respect and approval. The act of applause is also known as "clapping".
For humans, applause is performed by clapping both palms together. Bajorans applaud by clapping the back of one hand into the palm of the other. Cardassians applause is generated by tapping a table or armrest with a clenched fist. (DS9: "In the Cards", "Tribunal", "Sons and Daughters")