How to start understanding UML diagrams?

Question

Programming

I am learning OOP. There are no problems with design patterns, but their visualization on UML diagrams is confusing. A very specific visualization - for example, the feeling that the direction of the arrows should be the opposite.
How to begin to understand these schemes?
Or maybe they don’t need to be understood, because. are they rarely used?
Is there an alternative to them?

Answer 1

Or maybe they don’t need to be understood, because. are they rarely used?

Exactly.
If you often use, you will learn to understand.
If rare - you will understand, and then forget.
But UML is just one of the options for fixing contracts. It may be quite convenient and standardized, but not everyone uses it, because drawing UML is also a time and a task.

Answer 2

A very specific visualization - for example, the feeling that the direction of the arrows should be the opposite.

So, most likely, you have not fully formed an understanding of OOP.
The arrows quite accurately show who expands whom, implements whom, and generally depends on whom.

How to begin to understand these schemes?

Just like you learned to program - read more diagrams (can be found in books about software architecture), make your own.

Or maybe they don’t need to be understood, because. are they rarely used?

It's also partly true.