Editing Disassembler (section)

{{Short description|Computer program to translate machine language into assembly language}}
{{More footnotes|date=December 2009}}
A '''disassembler''' is a [[computer program]] that [[translator (computing)|translate]]s [[machine language]] into [[assembly language]]—the inverse operation to that of an [[Assembly language#Assembler|assembler]]. The output of disassembly is typically formatted for human-readability rather than for input to an assembler, making disassemblers primarily a [[reverse engineering|reverse-engineering]] tool. Common uses include analyzing the output of [[high-level language|high-level programming language]] [[compiler]]s and their optimizations, recovering [[source code]] when the original is lost, performing [[malware analysis]], modifying software (such as binary patching), and [[software cracking]].

A disassembler differs from a [[decompiler]], which targets a [[high-level language]] rather than an assembly language.

Assembly language [[source code]] generally permits the use of [[constant (programming)|constant]]s and programmer [[comment (computer programming)|comment]]s. These are usually removed from the assembled [[machine code]] by the assembler. If so, a disassembler operating on the machine code would produce disassembly lacking these constants and comments; the disassembled output becomes more difficult for a human to interpret than the original annotated source code. Some disassemblers provide a built-in code commenting feature where the generated output is enriched with comments regarding called API functions or parameters of called functions. Some disassemblers make use of the [[symbolic debugging]] information present in object files such as [[Executable and Linking Format|ELF]]. For example, [[Interactive Disassembler|IDA]] allows the human user to make up mnemonic symbols for values or regions of code in an interactive session: human insight applied to the disassembly process often parallels human creativity in the code writing process.