模拟器(英文;emulator、simulator),根据此原理制作的软件又可称为模拟程序,是指主要透过软件模拟硬件处理器的功能和指令系统的程序使计算机或者其他多媒体平台(掌上电脑,手机)能够运行其他平台上的软件。
DS上的DOS模拟器,新版更新如下:
Version 0.21 info
This is mostly a fix version after the somewhat buggy version 0.20. This version includes the finished AdLib emulation, and I fixed the problem introduced in 0.20 with the Direct SB mode where the start of the BIOS F000 segment was overwritten with corrupt data. This version also has a lot more of the opcodes refactored to use the new more robust memory handling, which also means that this version will run slower than the previous version. Norton SysInfo tells that this version runs at 9.9 times original PC, while the version before any of these internal changes ran at 11.5 times original PC. I am still not even half way done with the internal refactoring, so the next version might still be slower, until I get all the refactoring done and can again start optimizing things.

制作专门的模拟机器往往是价格高昂与困难的,因此使用计算机来模拟是最廉价及方便的方法。