This document provides an introduction to distributional semantics. It discusses how distributional semantic models (DSMs) represent word meanings as vectors based on their linguistic contexts in large corpora. This distributional hypothesis states that words that appear in similar contexts tend to have similar meanings. The document outlines how DSMs are built, important parameters like context type and weighting, and examples like latent semantic analysis. It also discusses how DSMs can support applications like semantic search. Finally, it introduces how compositional semantics explores representing the meanings of phrases and sentences compositionally based on the meanings of their parts.