notes.md

Day 6 - Variable & Data Types

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Variable

Variables are like containers that stores data in them. Now the stores data they can be accessed using these variables. These variables are stored in RAM.

Rules for Python variables:

• A variable name must start with a letter or the underscore character
• A variable name cannot start with a number
• A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
• Variable names are case-sensitive

Syntax

a = 10
print(a)
# print(A) #error - As a and A are differently treated(case-sensitive)
b = "Python"
print(b)
c = None
print(c)
d = true
print(d)

More to know

a1 = "first_name"
a2 = "second_name"
b1 = 12
b2 = 23
print(a1+a2) #valid
print(b1+b2) #valid
# print(a1+b1) #error -- since the datatypes of both are different

# How to get the type of data(which maybe stored in a variable)
print(type("name"))

a = 100
print(type(a))

Data Types

Data are categoried into various types depending on it's nature and tha actions that can be performed with them. These are different types of values that a variable can store

Python has some built in data types

Category	Data Type
Text Type	str	str: "This is a string", "Name"
Numeric Type	int, float, complex	int: 3, -2, 0 float: 7.356 complex: 4-3i
Sequence Types	list, tuple, range	list: [1, 2, -12.22, ["apple", "banana"], "string"] tuple: ("element1", -2, 12e2, ("apple"), ['mango']) range:
Mapping Type	dict	dict: {name: "first1", age: 20}
Set Types	set, frozenset	set: {"value1", "value2", 3}
Boolean Types	bool	bool: false, true
Binary Type	bytes, bytearra, memoryview
None Type	None	None: None

In Python everything is object, any data type is object You do not need to rememeber the list

We will be exploring all of these afterwards

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References

• CWH Python 100 days challenge - Day 6

• W3 School - Python Variables

• W3 School - Python Data Types