Python

What is a receiver in Go, what types are there, and what are they used for?

What is an interface in Go, how does it look externally and internally?

What is a JOIN in databases, and what types are there?

What is alignment and padding in Go, and how do they work?

What is a slice in Go, what does it consist of, and how does it work?

What does 'implement interface X for structure Y' mean?

What is a channel in Go, and what is it used for?

How to check if the value inside interface{} equals nil (write code)?