The sequence "1, 2, 3, 4, 5, ..." represents the natural numbers, which are the basic counting numbers used in everyday life. These numbers are used for various purposes, such as counting objects, ordering items, and performing basic arithmetic operations like addition and subtraction. Natural numbers are foundational in mathematics and are often the first numbers taught to children. They can be represented on a number line, where each number has a specific position, and they continue infinitely in the positive direction. This sequence is essential for understanding more complex mathematical concepts.