A disassembler is a software tool that translates machine code, which is the low-level code that computers understand, back into a more human-readable format called assembly language. This process allows programmers and security analysts to examine how a program operates at a fundamental level. Disassemblers are often used in reverse engineering, debugging, and malware analysis to understand the behavior of software. Disassemblers work by taking the binary code of a program and breaking it down into its individual instructions. Each instruction corresponds to specific operations that the computer can perform. Popular disassemblers include tools like IDA Pro and Ghidra, which help users analyze and modify software for various purposes, including improving security and optimizing performance.