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Programming is the process of writing instructions for a computer to execute. It involves using specific syntax and logic.

Core Concepts

• Variables & Constants: Variables store data and can change; constants cannot change once set.
• Data Types:
  • INTEGER: Whole numbers (e.g., 10).
  • REAL / FLOAT: Numbers with decimals (e.g., 3.14).
  • BOOLEAN: Either TRUE or FALSE.
  • CHARACTER: A single letter/symbol (e.g., 'a').
  • STRING: A sequence of characters (e.g., "Hello").
• Input, Output, Assignment:
  • INPUT: Gets data from the user.
  • OUTPUT: Displays data to the user.
  • ASSIGNMENT: Stores a value in a variable (score = 0).

Control Structures

These dictate the flow of your program:

• Sequence: Runs code in order.
• Selection: Uses IF / ELSE to choose paths.
• Iteration: Repeats code.
  • FOR loops: Fixed repetitions.
  • WHILE loops: Repeat while condition true.
  • REPEAT...UNTIL: Always runs at least once.

Programming Concepts

Data & Program Management

• Data Structures: Arrays (1D lists, 2D tables).
• Subroutines: Procedures (no return) and functions (return a value).
• Structured Programming: Modular, reusable code for clarity/debugging.
• File Handling: OPEN, READ/WRITE, CLOSE files.

Example Pseudocode

FUNCTION calculateArea(radius)
    PI = 3.14159
    area = PI * radius * radius
    RETURN area
ENDFUNCTION

INPUT "Enter radius: " TO userRadius
circleArea = calculateArea(userRadius)
OUTPUT "The area is: " & circleArea
      

Debugging & Standards

Debugging means finding and fixing errors: syntax, logic, or runtime. Following good coding standards (clear names, comments) makes programs easier to read and maintain.