In computer science, binary numbers are used to represent data and perform operations within the computer system. Binary numbers are composed of only two digits: 0 and 1. Each digit in a binary number is referred to as a bit, and a group of 8 bits is called a byte. Data is stored and processed in binary format in computers because digital circuits can easily distinguish between the two binary states. This allows computers to perform complex operations quickly and efficiently. For example, in binary, the number 5 is represented as 101. To add two binary numbers, you follow the same rules as adding decimal numbers, with carry-over operations performed when necessary. Understanding binary numbers and data representation is crucial in computer science as it forms the foundation for understanding how computers manipulate and process data. By learning to convert between binary and decimal numbers, as well as perform basic arithmetic operations in binary, you can better comprehend how computers store and process information at the most fundamental level.