Learn ALGOL with Real Code Examples

ALGOL introduced block structure, lexical scoping, and structured programming concepts.

It was widely used in academic and scientific communities for describing algorithms.

Influenced the design of many modern programming languages and formal algorithm notation.

Procedures with parameters

Variable declaration and type system

Arrays and multi-dimensional arrays

Recursion support

Structured loops and conditional statements

Block structure: begin…end

Variable declaration with types

Procedures with parameters

Control statements: if, for, while

Arrays and recursion

src/ - ALGOL source code files

examples/ - algorithm samples

docs/ - algorithm documentation

tests/ - sample input/output

libs/ - reusable procedure libraries

Write ALGOL program in text file (.alg, .aal)

Define procedures and main block

Compile with ALGOL compiler

Run program and test outputs

Refactor and modularize using procedures

Beginner: simple arithmetic and loops

Intermediate: recursion, arrays, and functions

Advanced: numerical simulations

Expert: algorithm research and compiler testing

Specialist: formal method studies

More structured than early Fortran

Simpler syntax than COBOL

Influenced Pascal, C, and modern languages

Less practical for modern industrial software

Ideal for algorithm description rather than large applications

1958 – ALGOL 58 created

1960 – ALGOL 60 standardized

1968 – ALGOL 68 introduced new features

1970s – Academic adoption worldwide

1980s+ – Gradual decline in practical use

Block: begin…end code section

Procedure: modular code block

Call by name/value: parameter passing mechanism

Array: indexed data structure

Recursion: procedure calling itself