This topic focuses on understanding how to describe the domain and range of functions from set intervals using words, specifically incorporating the concept of unions between sets. The problems are aimed at converting mathematical expressions of intervals into verbal descriptions, determining either domain or range for each given interval. Each problem presents a union of intervals (such as `[-7, -1] ∪ (0, 5)`), and requires conversion into a verbal statement describing all the real numbers included in the interval. This involves recognizing and correctly interpreting the different types of brackets and parentheses to define inclusivity and exclusivity within the intervals.