Python -Booleans and variables

What is a Variable?

VARIABLES are entities that help us store information and retrieve it later.

• A variable with a fixed name can store information of nature like numeric, textual, boolean, etc.

• A Python variable is a reserved memory location to store values. In other words, a variable in a python program gives data to the computer for processing.

• The type of data contained in a variable can be changed at the user's will.

Example:

You can store numbers in variables.

The standard rule is you write the variable name followed by = sign and the value it will take

x = 5

y = 3

Basic Arithmetic operations we can do on x and y. Later we will be doing operations on thousands of such numbers in one go!

z= x + y

ans : 5+3 = 8

Floats:

Integers and floats are two different kinds of numerical data. An integer (more commonly called an int) is a number without a decimal point. A float is a floating-point number, which means it is a number that has a decimal place.

Example:

1.0 , 0.1 . 0.6 1.36 etc.

Integers:

An integer (from the Latin integer meaning "whole") is colloquially defined as a number that can be written without a fractional component. 

Example:

21, 4, 0, and −2048 are integers, while 9.75, 512, and √2 are not integers.

Rules for naming a variable in Python:

• Variables names must start with a letter or an underscore like the product, product

• The remainder of your variable name may consist of letters, numbers, and underscores

• spacy1, pyThon, machine learning is some valid variable names

• Names are case-sensitive.

• case_sensitive, CASE SENSITIVE, and Case Sensitive are each a different variable.
• Names cannot begin with a number. Python will throw an error when you try to do so
• Names can not contain spaces, use instead names can not contain any of these symbols:

• :'",<>/?|\!@#%^&*~-+

• It is considered best practice that names are lowercase with underscores

• Avoid using Python built-in keywords like list, str , def etc. 

We will talk more about such conventions later on.

Boolean Variables:

• A Boolean variable only takes two values either True or False. It is used for comparisons

Comparison Operators:.

• These operators will allow us to compare variables and output a Boolean value (True or False).

• If you have any sort of background in Math, these operators should be very straightforward.

• First, we'll present a table of the comparison operators and then work through some examples:

• In the table below, a=3 and b=4.

Operator	Description	Example
==	If the values of two operands are equal, then the condition becomes true.	(a == b) is not true.
!=	If the values of two operands are not equal, then the condition becomes true.	(a != b) is true
>	If the value of the left operand is greater than the value of the right operand, then the condition becomes true.	(a > b) is not true.
<	If the value of the left operand is less than the value of the right operand, then the condition becomes true.	(a < b) is true.
>=	If the value of the left operand is greater than or equal to the value of the right operand, then the condition becomes true.	(a >= b) is not true.
<=	If the value of the left operand is less than or equal to the value of the right operand, then the condition becomes true.	(a <= b) is true.

• Python comes with Booleans (with predefined True and False displays that are basically just the integers 1 and 0). It also has a placeholder object called None. Let's walk through a few quick examples of Booleans (we will dive deeper into them later in this course).

Thanks for reading...

You can learn more using the below links

1.Python Integers, Floats

2.History of Python

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