DEB stands for Data Encryption Standard, a symmetric-key algorithm used for the encryption of digital data. Developed in the 1970s, it became a widely adopted standard for securing sensitive information. DEB uses a fixed-size key of 56 bits to encrypt data in 64-bit blocks, making it effective for its time. However, as computing power increased, DEB became vulnerable to brute-force attacks. In 2001, it was officially replaced by the more secure Advanced Encryption Standard (AES). Despite its limitations, DEB played a crucial role in the development of modern cryptography and laid the groundwork for future encryption standards.