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6. Features of a compiler (3)

Executable file

The output of a compiler is the creation of an executable file.

An executable file contains the entire machine code of the application / software. The machine code runs on the CPU once the executable file has been loaded into main memory as a process by the operating system.

Advantages of an executable file.

1. One of the advantages of an executable file is that it runs very quickly compared to interpreting each line of source code one-at-a-time (Interpreters that do this are discussed later).

2. The original source code is absent. And so it is a very convenient way of distributing software and at the same time protect copyright / Intellectual Property.

3. Making unauthorised changes to the software is difficult. Machine code is hard to understand and so it is not easy for someone to alter the software when distributed as an executable.

Interesting fact:

In the software licence conditions of most applications (the EULA you agree to during installation), you will often find a clause that makes it a breach of copyright to 'reverse engineer' the executable back into source code.