Wikipedia lists "Hash function algorithms" within the "Hash function" page. I'm wondering what are the differences and if I can use the terms "hash(ing?) algorithm" and "hash function" interchangeably.
Strictly speaking, an algorithm is a method of computing a function. The function is the thing you stick an input into and get an output from. The algorithm is how it does it. In the context of cryptography, however, hash function and hash algorithm are often used interchangeably. People will know what you mean by it.
I believe hash function is the more common term though. Plain old hash is totally fine as well.