.exe

Windows Executable File
Filename extension	.exe
Internet media type	application/vnd.microsoft.portable-executable
Magic number	0x4d 0x5a
Developed by	Microsoft
Type of format	Executable file
Container for	MZ, NE, LX, LE, PE, PE32+, W3, W4, DL, MP, P2, P3
Open format?	No

For Microsoft Windows, OS/2, and DOS, .exe is the filename extension that denotes a file as being executable – a computer program – containing an entry point.^[1]

In addition to being executable (adjective) such a file is often called an executable (noun) which is sometimes abbreviated as EXE.

^ ".EXE File Extension". FileInfo - The File Extensions Database. Sharpened Productions. Retrieved 2019-08-16.