Master Python Basics: Essential Syntax, Data Types, and I/O Explained

Part 1: Program Format Framework

Python programs use indentation to define blocks; proper indentation improves readability and maintainability. The recommended indentation is four spaces, though tabs are possible. A SyntaxError: unexpected indent indicates indentation problems.

Comments: single‑line comments start with # ; multi‑line comments are enclosed in triple quotes ( ''' ... ''' or """ ... """ ).

Line continuation: a backslash ( \ ) at the end of a line splits a long statement; no spaces may follow the backslash.

Part 2: Syntax Elements

Variables can be created and assigned at any time. Names may contain letters, digits, and underscores, must not start with a digit, and are case‑sensitive. Python 3 has 35 reserved keywords, e.g., and, as, assert, break, class, continue, def, del, elif, else, except, False, finally, for, from, global, if, import, in, is, lambda, None, nonlocal, not, or, pass, raise, return, True, try, while, with, yield, async, await.

Part 3: Data Types

Numeric types: int (decimal, octal, binary, hexadecimal), float (decimal with fractional part or scientific notation), complex (a+bj, created with complex(a,b) ).

String type: defined with single or double quotes; each character occupies one position. Strings support two indexing schemes—zero‑based forward and negative backward—enabling slicing.

Boolean type: True and False . Logical operators: and (both true), or (any true), not (negation). Values such as 0, empty string, None , empty collections evaluate to False .

Numeric type conversion is supported (e.g., int() , float() ).

Part 4: Statement Elements

Assignment uses the equal sign ( = ).

Expressions consist of operators and operands and are evaluated to produce a value.

Part 5: Basic Input/Output Functions

input() reads a line from standard input and returns it as a string.

eval(str) evaluates a string containing a Python expression and returns the result.

print() outputs the given expression to standard output.