The Netwide Assembler (NASM) is an assembler and disassembler for the Intel x86 architecture. It can be used to write 16-bit, 32-bit (IA-32) and 64-bit (x86-64) programs. NASM is considered to be one of the most popular assemblers for Linux.
NASM was originally written by Simon Tatham with assistance from Julian Hall, and is currently maintained by a small team led by H. Peter Anvin. It is available as free software under the terms of the simplified (2-clause) BSD license.
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