About Python

Python is a very popular general-purpose programming language. It became known for its simplicity, ease of learning and fast programming. Many professional developers use Python at least as an auxiliary language, because they quickly and easily automate various jobs with it. Due to the aforementioned good qualities, there are more and more users of Python among people from other professions who use programming in various fields. The Python programming language is free to use, and a large community has been formed around it, contributing to its further development and general support on the Internet.

Python’s programming language makes it clear that programming is not just for professional programmers, the same way writting is not just for professional writers. There are more and more jobs that can become somewhat easier, more successful or more productive with moderate programming skills. Therefore, this handbook is not only for future programming professionals, but for anyone who can benefit from programming in their jobs (or elsewhere).

So, let’s look at the basics of Python and see how commands and programs are written in this programming language.

Python interpreter

To execute programs we write in Python, we need a program called Python interpreter. This program interprets and then executes Python commands. Python interpreters can accept whole programs and execute them, and they can also work in interactive mode, in which every command we enter is executed immediately.

The environment in which the Python interpreter executes is called a shell. There are various shells in which the corresponding Python interpreter can be executed. Therefore, we have several ways to launch the Python shell.

Shells online

Website https://www.python.org/shell contains an online shell, which you can use right away for interactive work (it is enough to have internet access).

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Python installation and IDLE environment

To learn Python programming, it is certainly useful to download Python from https://www.python.org/downloads/ and install it if it is not already installed on your computer. With the Python installation, you also get a program called IDLE (integrated development and learning environment). This integrated environment also includes a shell where you can execute Python programs. When you run IDLE on your computer, you get the following window, in which you can work interactively and write and execute Python programs.

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Shell in the command window

Another way to start a Python shell is to open a command window (on Windows systems this is done by running the program cmd) and then type Python in the command window (here we asume that Python is installed so that it is accessible from every folder, otherwise you should first position yourself in the Python interpreter folder).

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You can choose any shell you like, they are all used in the same way.