Python 101: The Basics
Part I: Variables, Control Flow and Looping
Introduction / History
Python is a “high-level programming language and its core design philosophy is all about code readability and a syntax which allows programmers to express concepts in a few lines of code” created by Guido van Rossum.
For me the first reason to learn Python was that it is, in fact, a beautiful programming language. It is really natural to code it and always express my thoughts.
Another reason is that we can coding in Python to multiple uses: data science, web development, machine learning shine here. Quora, Pinterest and Spotify use Python for their backend web development for example.
You can think about variables as a word that stores a value. Simple as that.
In Python it is really easy to define a variable and set a value to it. Imagine you want to store number 1 in a variable called “one”. Let’s do it!
Wow! How simple was that? You just assigned the value 1 to “one” variable
And you can assign some value for whatever variable you want. “two” variable stores 2 integer and “some_number” stores 10000.
Besides integers, we can also use booleans (True / False), strings, float and so many other data types.
2. Control Flow: conditional statements
“If” uses an expression to evaluate to True or False. If it is True, it executes what it is inside the if statement. For example:
2 is greater than 1, so the “print” code is executed.
The “else” statement will be executed if “if” expression is false.
1 is not greater than 2, so the code inside “else” will be executed.
You can also use “elif” statement. Like that:
3. Looping / Iterator
In Python we can iterate in different forms. I’ll talk about 2: while and for.
While Looping: while the statement is True, the code inside the block will be executed. So this code will print the number from 1 to 10.
The while loop needs a “loop condition” and if it keeps True, it continues iterating. In this example, when
11 the “loop condition” evaluate to
Another basic code to better understand it:
The “loop condition” is
True so it keeps iterating, until we set it to
For Looping: you pass the variable “num” to the block and the “for” statement will iterate it for you. This code will print the same as “while” code: from 1 to 10.
Great! It is so simple! From a range starting with
1 until the
11th element (
10 is the
We learnt a lot of things about Python basics:
- How Python variables work
- How Python conditional statements work
- How Python looping (while & for) work
And that’s it guys! I want to update this article. The idea is to share a great content and the community helps improve it! ☺
For the second part of this Python Series we are gonna talk about Python Data Structures. See you there!
Have fun, keep learning & always coding!