Background on Geometric Measure Theory We collect some basic definitions and facts about the geometric measure theory. Readers can refer to [All72, Sim83] for more details. Sections Varifolds Sets of Finite Perimeter Dimension Reduction and Regularity of Perimeter Minimizers Proof of Bernstein Theorem Previous Sub-minimal Sets and Sub-calibrations Next Varifolds Gaoming Wang Assistant Professor My research interests include Geometric Analysis and Partial Differential Equations.