Python Basics
2026-02-21 23:39 Diff
https://hexlet.io/courses/python-basics/lessons/instructions/theory_unit

When we're making a dish, we follow the recipe carefully. Otherwise, the food won't turn out as expected. The same rule applies to programming.

We want to see the expected result onscreen, so we should give the computer clear, step-by-step directions. We can do it using instructions. An instruction is a command to the computer, a unit of execution. In this case, Python code is a set of instructions. We can present it as a step-by-step recipe.

We run the Python code using an interpreter, a program that executes instructions strictly one at a time. Like the steps in a recipe, the instructions for the interpreter are written in order and separated by jumping to the following line.

Developers must understand the order of operations in the code and be able to mentally break the program into independent parts that are convenient for analysis.

Let's look at an example of some code with two instructions. When it's started, two sentences are displayed sequentially on the screen:

We said above that instructions are separated from each other by a line break. But there is another way: you can separate them with a semicolon:

There is no technical difference between the first and second versions. The interpreter will understand the instructions the same way, but it is physically inconvenient to read the second version.

It is better to place the instructions under each other. It makes it easier for colleagues to read your code, maintain it, and make changes.