This document discusses polynomials and linked lists. It explains that polynomials are mathematical expressions consisting of terms and addition of polynomials involves combining like terms. It also defines a linked list as a linear data structure where each node stores data and a link to the next node. The document then demonstrates how two polynomials can be added by representing them as linked lists, where the terms are arranged in descending order based on exponents, making addition easier by allowing the like terms to be combined.