What is the difference between als and wenn in German?

There are a few subordinate clause conjunctions that students find difficult to use. The conjunctions "als' and "wenn" are often considered to be particularly confusing. While both might often be translated as 'when' in English, they’re used in a completely different way. Below you'll find an explanation of the difference between als and wenn:
https://www.olesentuition.co.uk/single-post/what-is-the-difference-between-als-and-wenn-in-german

How to use "als" and "wenn" in German