How are properties defined in a class diagram when using UML? -

Development has not started when I'm trying to wrap my head about the construction of a class diagram. My understanding is that you put the UML diagram together before any development. I have come to an article.

If I look under the title 'Square' then I get details about the properties of a class eg.

I think that when it is referred to public and private, it means that in the case of the former, the property is accessible by any other object and whenever it is private, it is limited to the user class. Is it true?

Why there is no discriminating between the salt, and so on. Login Logout?

Do class diagrams come only after use case and activity diagram? 1 and 2: Think about your functional context, make a software, say, make a library Will happen? You will probably manipulate the books, so you will have a "book" in UML. And you will need to know the book and author's title and author. So naturally, using UML, you will create a UML class named Utility Title and Book with Author. And you do not need to know that it will actually be in accordance with the actual class of a real deity.

3: That's right.

4: There are properties above the divider, below the operation (i.e.)

5: There is no unique answer to this question. It depends on your project method. UML does not tell you which diagram you use, T only gives you the tools. Personally, I want to start with the use cases, that I think basic, and then to clarify clearly, with only the first classes and very important characteristics (no operation, no visibility) I want to create the first first general class diagram, a global view of the data included. Then I will use the activity diagram, the detailed class diagram and sequence diagrams, and Do Istarit. But how I want to work, is not a general requirement.