The goal of this post is to introduce, in a very informal way, the notion of a reductive group, and discuss some examples.

# Algebraic Groups

# p-divisible groups, formal groups, and the Serre-Tate theorem

In this post we discuss the basic theory of p-divisible groups, their relationship to formal groups, and the Serre-Tate theorem.

# Classifying One-dimensional Algebraic Groups

In this post, we classify one-dimensional algebraic groups over an algebraically closed field.

# Group Schemes and Affine Group Schemes

In this post we motivate the notion of affine group schemes, and discuss the various equivalent ways of defining them.