This document discusses sequences and series, their definitions, types, and applications in daily life. It begins by defining a sequence as a collection of objects listed in any order, with each element having a specific position called its rank or index. Arithmetic and geometric sequences are introduced, with arithmetic sequences having a constant difference between adjacent terms and geometric sequences multiplying or dividing adjacent terms by a fixed ratio. Examples are given of sequences in various domains like finance, exponential growth, movement, and DNA sequencing. The document concludes by noting that sequences and series have unlimited applications in real life and are used across many sectors beyond just business or a single domain.