Freiman's Theorem is a result in additive combinatorics that deals with sets of integers. It states that if a finite set of integers has a small sumset, meaning the set of all possible sums of pairs of its elements is not too large, then the original set must have a specific structure. Essentially, it implies that such sets can be closely approximated by arithmetic progressions. The theorem provides a way to understand the additive properties of sets and has implications in various areas of mathematics, including number theory and combinatorics. It helps mathematicians analyze how elements combine and interact under addition, revealing deeper patterns within the numbers.