Programming Concepts Beginner

What is Unit Testing?

Testing individual components or functions of a program in isolation to verify they work correctly.

Unit tests verify that individual functions, methods, or classes produce correct output for given inputs. They run fast, test in isolation (using mocks/stubs for dependencies), and provide immediate feedback when code breaks.

Popular frameworks include pytest (Python), JUnit (Java), Jest (JavaScript), and PHPUnit (PHP). Test-Driven Development (TDD) writes tests before implementation. Good tests are independent, repeatable, and cover edge cases.

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Related Terms

A mathematical notation that describes the worst-case performance of an algorithm as input size grows.

Object-Oriented Programming (OOP)

A programming paradigm that organizes software design around objects containing data and behavior.

A data structure that follows First-In-First-Out (FIFO) ordering, where elements are added at the rear and removed from the front.

Immutable Object

An object whose state cannot be modified after creation, providing thread safety and predictable behavior in concurrent systems.

A way of organizing and storing data in a computer so it can be accessed and modified efficiently.

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A methodology of twelve best practices for building modern, scalable, maintainable software-as-a-service applications.

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