Document

Introduction

Python is a popular programming language. It was created by Guido van Rossum, and released in 1991. It is used for:

web development (server-side),
software development,
mathematics,
system scripting.

What can python do

Python can be used on a server to create web applications.
Python can be used alongside software to create workflows.
Python can connect to database systems. It can also read and modify files.
Python can be used to handle big data and perform complex mathematics.
Python can be used for rapid prototyping, or for production-ready software development.

Why Python

Python works on different platforms (Windows, Mac, Linux, Raspberry Pi, etc).
Python has a simple syntax similar to the English language.
Python has syntax that allows developers to write programs with fewer lines than some other programming languages.
Python runs on an interpreter system, meaning that code can be executed as soon as it is written. This means that prototyping can be very quick.
Python can be treated in a procedural way, an object-oriented way or a functional way.

Python Syntax compared to other programming languages

Python was designed for readability, and has some similarities to the English language with influence from mathematics.
Python uses new lines to complete a command, as opposed to other programming languages which often use semicolons or parentheses.
Python relies on indentation, using whitespace, to define scope; such as the scope of loops, functions and classes. Other programming languages often use curly-brackets for this purpose.


                print("Hello, World!")

Python Indentation

Indentation refers to the spaces at the beginning of a code line. Where in other programming languages the indentation in code is for readability only, the indentation in Python is very important. Python uses indentation to indicate a block of code. Python will give you an error if you skip the indentation:


                if 5 > 2:
                print("Five is greater than two!")

The number of spaces is up to you as a programmer, but it has to be at least one.You have to use the same number of spaces in the same block of code, otherwise Python will give you an error:

Python Variables

In Python, variables are created when you assign a value to it:


                x = 5
                y = "Hello, World!"

Python has no command for declaring a variable.

Python Comments

Python has commenting capability for the purpose of in-code documentation. Comments start with a #, and Python will render the rest of the line as a comment:


                #This is a comment.
                print("Hello, World!")

Comments can be used to explain Python code. Comments can be used to make the code more readable. Comments can be used to prevent execution when testing code.

Comments can be placed at the end of a line, and Python will ignore the rest of the line:


                print("Hello, World!") #This is a comment

Multi Line Comments

Python does not really have a syntax for multi line comments. Since Python will ignore string literals that are not assigned to a variable, you can add a multiline string (triple quotes) in your code, and place your comment inside it:


                """
                This is a comment
                written in
                more than just one line
                """
                print("Hello, World!")

Python Data Types

In programming, data type is an important concept. Variables can store data of different types, and different types can do different things. Python has the following data types built-in by default, in these categories:
Text Type: str
Numeric Types: int, float, complex
Sequence Types: list, tuple, range
Mapping Type: dict
Set Types: set, frozenset
Boolean Type: bool
Binary Types: bytes, bytearray, memoryview


                x = 5
                y = "Hello, World!"

Python Numbers

There are three numeric types in Python:

int
float
complex

Variables of numeric types are created when you assign a value to them:


                x = 1    # int
                y = 2.8  # float
                z = 1j   # complex\