SAM HARRIS TECH REVISION

OCR GCSE CS - 2.2 Programming Fundamentals

2.2 Programming Fundamentals (OCR J277)

Variables and Constants: Using identifiers to store data that can change (variables) or stay the same (constants) during execution.
Assignment: Giving a value to a variable (e.g., x = 5).
Sequence: The order in which instructions are executed.
Selection: Using IF/ELSE or SWITCH/CASE statements to make decisions.
Iteration: Using loops like FOR (count-controlled) and WHILE (condition-controlled).
Operators: Arithmetic (+, -, *, /, MOD, DIV, ^) and Comparison (==, !=, <, >, <=, >=).
Boolean Logic: Combining conditions using AND, OR, and NOT.

Integer: Whole numbers (e.g., 10, -5).
Real (Float): Numbers with decimal points (e.g., 3.14).
Boolean: True or False values.
Character: A single letter, number, or symbol.
String: A sequence of characters (e.g., "Hello World").
Casting: Converting one data type to another (e.g., converting a string "10" to an integer 10).

String Manipulation: Methods like .length, .upper, .lower, .substring, and concatenation (+).
File Handling: How to open, read, write, and close external text files.
Records: Storing related data of different types in a structured way (similar to a row in a database).
Arrays: Using 1D and 2D arrays to store multiple items of the same data type under one name.
Subprograms: Using Functions (return a value) and Procedures (do not return a value) to make code modular and reusable.
Random Number Generation: Using libraries to create unpredictable values.