This document provides an overview of several genetics concepts including: 1) Mendelian genetics concepts like monohybrid and dihybrid crosses as well as test crosses. 2) The concepts of incomplete dominance and codominance where neither or both alleles are expressed in heterozygotes. 3) ABO blood types as an example of codominance with multiple alleles. 4) Sex determination and sex-linked traits related to the X and Y chromosomes. 5) How pedigrees are used to track the inheritance of traits through families.