The binary number "11001001" is an 8-bit sequence used in digital computing and electronics. Each digit, or bit, can be either a 0 or a 1, representing the off and on states of a switch. In decimal form, "11001001" equals 201, which is often used in programming and data representation. In the context of computer science, binary numbers like "11001001" are fundamental for data processing and storage. They are used in various applications, including computer programming, data encoding, and network communication. Understanding binary is essential for anyone working with computers or digital technology.