An executable file is any file that will carry out specific tasks when opened and will commonly have the exe extension in DOS based systems. So, for example, when you open up Windows you have activated the windows.exe file.
file name that can be used as a command, consisting either of a script of commands to be executed by typing the name, or of true compiled binary program code. In the latter sense (also called binaries), the executable(s) is sometimes used to distinguish compiled binary code from its human-readable programming-language source: "He gave me the executable, but I needed the source files."
File stored on a disk which can be run on the computer. Executables are marked with the executable attribute (See the chmod command). Executables are stored in a particular format (e.g. ELF), and consist of headers plus machine code.