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What is an Algorithm?

Before writing any code, a good programmer thinks about the steps needed to solve a problem. This ordered set of steps is called an algorithm.

An algorithm is a step-by-step set of instructions designed to solve a problem or complete a task. Every program is essentially an algorithm written in a programming language.

Illustration showing a problem on the left, an arrow pointing to a numbered list of steps in the middle labeled algorithm, and the solution on the right

Properties of a Good Algorithm

Input — it takes zero or more inputs
Output — it produces at least one result
Definiteness — every step is clear and unambiguous
Finiteness — it terminates after a finite number of steps
Effectiveness — every step is simple enough to be carried out

A Real-Life Algorithm Example

Making a cup of tea is an algorithm! Here's how it looks as a step-by-step process:

Making Tea — Step by Step

A kettle with steam coming out representing boiling water — 1. Boil Water

A tea bag being placed into an empty cup — 2. Add Tea Bag

Hot water being poured from a kettle into a cup with a tea bag — 3. Pour Water

A finished cup of tea with steam on a saucer ready to be served — 4. Serve

Algorithms in Programming

In programming, algorithms are expressed as code. Before writing code, it is always a good idea to plan your algorithm in plain language or as a flowchart. This makes coding much easier and helps avoid mistakes.

Algorithm vs Code

Algorithm Step	Python Code
Get the user's name	name = input("Enter your name: ")
Display a greeting	print("Hello, " + name)
Ask for the user's age	age = int(input("Enter your age: "))
Check if old enough to vote	if age >= 18:
Display result	print("You can vote!")

A well-planned algorithm makes writing code much faster and less error-prone. Always plan before you code!