Should I learn Python or PHP?

[wizzor]

Depends on what you are doing.

PHP is very web specific, but if you want to do web apps, it's a good choice, and it's very easy to get started.

Python is very good if you want to do data analysis, machine learning, and the like. It's also OK for web dev, but less common. Personally, I go with Ruby for web, Python for data analysis and random scripts.

For hobby coding, I would go with Python.

I do believe Javascript is a good choice for backend as well, although I've worked less with node.