This document summarizes research on solving the travelling salesman problem (TSP) using ant colony optimization (ACO). It first provides background on TSP and describes how ACO mimics real ants finding food to solve optimization problems. The document then reviews several papers that have applied ACO to TSP and compared it to other algorithms. It finds that ACO generally performs better than genetic algorithms at finding optimal solutions to TSP as the number of cities increases. Finally, it proposes studying the effects of different ACO parameters on finding optimal TSP solutions.