A disassembler is a tool used in computer programming that converts machine code, which is the binary code executed by a computer's processor, back into a more human-readable assembly language. This process helps programmers understand how a program operates at a low level, making it easier to analyze, debug, or modify existing software. Disassemblers are commonly used in fields like software development, cybersecurity, and reverse engineering. By translating machine code, they allow developers to inspect the inner workings of applications, including those created by others, such as malware or proprietary software, without needing access to the original source code.