1, DOS: It is 1979 MS-DOS developed by Microsoft for IBM personal computer, which is a single-user and single-task operating system.

2. PE: Windows pre-installation environment, which is the smallest Win32 subsystem with limited services, is based on Windows XP Professional and above running in protected mode.

Second, the technical characteristics are different

1, DOS: All DOS operating systems are run on machines using Intelx86 or its compatible CPU.

2. PE: It is not designed as the main operating system on the computer, but as an independent pre-installation environment and other installation programs and recovery technologies.

Third, the function is different

1, DOS: Disk drives are named by different letters. The standard practice is to reserve "A" and "B" for floppy disk drives. If the system has only one floppy disk drive, DOS allows this floppy disk drive to use both codes at the same time, and then DOS will ask the user to replace the floppy disk.

2. PE: including the minimum functions required for running Windows installation programs and scripts, connecting to the network, automating basic processes and performing hardware verification.

Baidu encyclopedia -Windows PE

Baidu encyclopedia -DOS