Python Basics: Data Types, Operators, Control Flow, and Common Functions

This guide presents a concise reference of essential Python fundamentals for beginners and intermediate learners.

Primary Data Types : boolean, integer, float, string, list, dictionary, and their literal representations.

Arithmetic Operators : + (addition), - (subtraction), * (multiplication), / (division), ** (exponent), // (floor division), % (modulo).

Comparison Operators : == , != , > , < , >= , <= .

Boolean Logic : and , or , not .

Special Characters : # (comment), \n (newline), \ (escape).

File Read/Write : f = open('path') – open a file; f.read() – read entire content; f.readline() – read one line; f.write('text') – write text; f.close() – close the file.

OS Module : import os – import standard library; os.getcwd() – current directory; os.makedirs('dir') – create directories recursively; os.chdir('dir') – change working directory; os.listdir() – list directory contents.

String Operations : Access characters with String[i] or slices String[i:j] ; Methods include upper() , lower() , count(x) , find(x) , replace(x, y) , strip() , join() , format(x) .

List Operations : Create with list = [] ; Indexing, slicing, list.append(x) , list.extend(L) , list.insert(i, x) , list.remove(x) , list.pop(i) , list.clear() , list.sort() , list.reverse() , list.copy() . Delete element with del list[i] .

Dictionary Operations : Create with dict = {} ; Access/assign via dict[key] = value ; Delete with del dict[key] ; Methods: keys() , values() , items() , pop() , update(D) , clear() , copy() .

Control Flow : Conditional statements using if , elif , else ; Loop constructs: while condition: , for i in range() , for k, v in dict.items(): ; Loop control with break and continue . Exception handling with try: , except: , else: .

Functions, Modules, Packages : Define functions with def func(): and return values using return ; Import modules via import module , import module as alias , from module import name , from module import name as alias ; Import from packages with import package.module or from package import module .