What's the difference between lectures and recitation?

Lectures introduce mostly new concepts and are taught by the professor. Recitations reinforce previously taught concepts to smaller groups, and are taught by the TAs.

LECTURE - an oral presentation intended to present information or teach people about a particular subject like history, background, theories, and equations. Usually given by a professor.

RECITATION - act of reciting from memory. It can also be a formal reading of verse or other writing before an audience. You simply recite what you remembered learning.

The main academic skill is math