Difference between API and ABI

Question

I am new to linux system programming and I came across API and ABI while reading Linux System Programming.

Definition of API :

Answer 1

This is my layman explanations:

• API - think of include files. They provide programming interfaces.
• ABI - think of kernel module. When you run it on some kernel, it has to agree on how to communicate without include files, i.e. as low-level binary interface.