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Python Language

  1. Easy to Learn
  2. Less coding
  3. Easy to read
  4. Libraries

How

  1. Listen and Watch
  2. Take notes
  3. practice
  4. Share

Data Type , Objects

Integers (int) => 1,2,3 Floating Point (Float) => 2.3 , 2.8 .100.1 Strings (str) => 'Hello' , "Hello"

Data Structures

Lists (list) ordered => [1 , 'Hi' , 4.2] Dictionaries (dict) unordered => {'key' : 'value'} => {'Name' : 'Mohamed'} Sets (set) unordered { 'A' , 'B' , 'C' } Tuples (Tuple) immutable(غير قابل للتغيير ) => (1 , 'Hi' , 4.2) Booleans (bool) => True , False

Data types numbers

+=> Addition -=> Subtraction / => Division % => Moduls ** => Exponent // => Floor Division [[Python/Number Calculations/Data_types numbers.py at main · mohamedmahmoud26/Python]]

The backslash \ is used in Python to escape special characters inside strings.

It tells Python "the next character is not regular text" — it has a special meaning.

Example 1 — You want this output:

%% ''Hallo, Mohamed Elseragy %%

No special characters here, so you can just print it normally:

print("%% ''Hallo, Mohamed Elseragy %%")

%% ''Hallo, Mohamed Elseragy %%

Example 2 — You want this output:

==%% " " " %%==

Since you're using double quotes " " inside the string, you must escape them using \":

print("==%% \" \" \" %%==")

Output:

==%% " " " %%==

Or use single quotes ' ' around the whole string and keep double quotes inside:

print('==%% " " " %%==')

Wrong Example:

print(\"\"\")

This will cause a SyntaxError — because Python thinks you're starting a triple-quoted string, but you never closed i

String

  • Single quotes (' ')= Double quotes(" ")

Escaping:

  • ( \n ) => New Line
  • ( \t ) => Such as(Enter Tab)

Function:

  • len => Count This variable.

Index:

  • Indexing means accessing a specific character in a string using its position (index).

  • Indexing starts from 0 on the left (forward indexing),
    and from -1 on the right (backward indexing).

Slicing:

  • Slicing means cutting a string into parts by selecting a range of characters using their indexes.

  • Syntax: string[start:end:step]

Upper:

  • The .upper() method is used to convert all characters in a string to uppercase (capital letters).

Lower:

  • The .lower() method is used to convert all characters in a string to lowercase (small letters).

Split:

Formatting

What is String Formatting?

String formatting is the process of inserting variables or values into a string in a structured and readable way.

Why Use It?

  • To create readable and dynamic messages

  • To control the format of numbers (like decimals or comma separators)

  • To keep code clean and professional

Methods of String Formatting

1. Old Style – Using % operator

  • %s → string

  • %d → integer

  • %f → float (e.g. %.2f = 2 decimal places)

2. Using str.format()

print("My name is {} and I am {} years old.".format("Sergio", 22))

Advanced formatting:

print("Pi is approximately {:.2f}".format(3.14159))

You can:

  • Rearrange: "Name: {1} {0}".format("Last", "First")

  • Use named placeholders: "{name}".format(name="Sergio")

3. f-strings (Formatted String Literals)

name = "Mohamed Mahmoud" age = 22 print(f"My name is {name} and I am {age} years old.")`

You can format directly:

pi = 3.14159 print(f"Pi to 2 decimals: {pi:.2f}") Python/Formating at main · mohamedmahmoud26/Python