A we call it a variable
A = 'Hello, the world'
print(a)

Data type concept

Data in Python has their own data types

Digital Type: Integer INT Floating Point Float Complex

print(4)    int  Integer type
print(3.1415)    floattype 
print((-1) ** 0.5)   complextype 

String Type: Actually, a normal text

String in Python requires a pair of single quotes, or double quotes to package

print('Today's weather is fine, good scenery is good at)
print('56')

Boolean type: used to express true / false / wrong

There are only two values ​​in the Boolean type, one is True, one is false

print(4 > 3)  True
print(1 > 5)  False

List type

names = ['Song Jiang','   ','Wu Song',' ']

Dictionary type

person = {'Name':'Dalang','Profession':Buy Cake ','height':'150'}

Yuanzu type

nums = (1,5,6,9,8)

Collection type

x = {9,'hello','good',True}

a = 34
b = 'hello'
c = True
d = ['Jay Chou','Eason Chan','Zhang Yu']

print(type(c))

In Python, the variable is no data type, the data type of our variable is actually the data type of the value corresponding to the variable.

Identifier: variable, module name, function name, class name

Nameout of the identifier:
rule:
1. Composed of numbers, letters, and underline, can not start with numbers
2. Strictly case sensitive (in computer programming, a total of 52 letters)
3. Cannot use keywords
Keywords: In Python language, there is a special meaning word, such as IF, For, Else, While, Try, etc.,
** Specification: ** Suggested compliance, compliance with the specification is professional, and the code is easy to read.
1. Small hump naming method: The first letter of the first word is lowercase, the first letter of each word is capitalized in UserNameAndPassword
2. Big hunch nomenclature: the first letter of each word is capitalized in Personmodel
3. Use the underscore connection: user_name_and_password
Use the variable, function and module name in Python, using underscore: Python's class name uses a large peak nomenclature

Assignment statement

a = 23

 I  = 'Peng Yuxi'
print(I)