MIT's 18.100B Real Analysis, taught by Tobias Holck Colding, covers arc length of curves defined through integrals before turning to the central topic of the lecture: the distinction between pointwise and uniform convergence of sequences of functions. Colding works through why pointwise limits can fail to preserve continuity and integrability while uniform limits do, then introduces the Weierstrass M-test as a practical criterion for establishing uniform convergence of series of functions. The lecture proceeds at blackboard pace with full proofs and definitions, building on earlier material in the course's treatment of sequences and series. Running 78 minutes, it is one lecture in MIT's full 18.100B course, available through MIT OpenCourseWare, and assumes familiarity with basic real analysis concepts like limits, continuity, and integration.