Binomial Coefficient:The binomial coefficient, often denoted as $\binom{n}{k}$, represents the number of ways to choose $k$ items from a set of $n$ items, without regard to order.
Pascal's Triangle:A triangular array of numbers where each number is the sum of the two numbers directly above it, starting with 1 at the top. The numbers in the triangle are the binomial coefficients.
Binomial Expansion:The process of using the binomial theorem to expand a binomial expression raised to a power, resulting in a sum of terms with specific coefficients and exponents.