What did I just downloaded and installed

I went to this website Download Python | Python.org and downloaded and installed the software. I searched for python and found it and clicked on it and ran it. A command text window opened. What did I just installed? Is that the compiler? Where is the editor? is Python line by line interrupter or it is a compiler? Thank you very much.

PS: I am very new in Python and I have very old programming knowledge (Fortran)

Does this help? 4. Using Python on Windows — Python 3.11.4 documentation

The documentation includes a complete guide to setting up and using Python for every current major operating system.

Python is bytecode-compiled and then the bytecode is interpreted. It’s similar to how C# and Java work, except that it does not usually leave behind any cached bytecode files (only if you import code from an existing module, then that file gets a cached version) and doesn’t use a separate step to package the bytecode and then run it. For the most part, it just directly runs the bytecode it just produced. However, it is not a line-by-line interpreter: those barely exist any more. If you give Python a .py file with code, it will bytecode-compile the entire file before it starts running.

The actual Python program (python.exe) combines the bytecode compiler, bytecode interpreter, and a REPL (read-eval-print loop - you may have had friends using some LISP dialect that had one of these). This combination makes it behave something more like a “line-by-line interpreter” (and the documentation refers to “the Python interpreter”) although it is not really line-by-line. You can type individual statements (this includes multi-line indented blocks; use a blank line after the block to tell the REPL that the block is finished) at the >>> prompt, and they will be evaluated and a representation of any result (except the special value None) is displayed.

You do not really need a dedicated editor to write code in Python, or any other programming language with textual source code, for that matter. You only need a text editor. We use a .py filename extension for importable modules (the import system looks for it specifically); on Unix-based systems, it’s fine for the main script to have no filename extension, as long as the executable bit is set and it has a shebang line. However, for those who prefer an IDE, Python comes with a basic one, called IDLE.

Thank you very much.