A 32-bit integer is a data type used in computer programming that can represent whole numbers. It uses 32 bits, or 4 bytes, of memory, allowing it to store values ranging from -2,147,483,648 to 2,147,483,647. This range is due to the way binary numbers work, where one bit is used for the sign of the number. In many programming languages, such as C and Java, a 32-bit integer is commonly used for variables that need to hold integer values. It is efficient for calculations and is widely supported across different computer architectures, making it a standard choice for many applications.