What is code?

The language computers understand

⏱ Est. ~4 min

01 · Read

Code is text that tells a computer what to do. When you write code, you're writing step-by-step instructions in a language the computer can follow.

You give other people instructions every day: a recipe tells someone how to cook a meal, driving directions tell someone where to turn. Code is the same thing, just written for a computer.

💡 Picture thisCode is like a recipe. A recipe says "mix flour and eggs, then bake at 350 degrees for 20 minutes." Code says "ask the user for their name, then display a greeting." Both are just ordered instructions that produce a result.

Key points

Code is just plain text — you write it in a regular text file, no special app needed
Code runs top to bottom, one instruction at a time
The computer does exactly what you say — nothing more, nothing less
If you write the instruction wrong, the computer won't guess what you meant — it'll either do the wrong thing or throw an error at you

02 · Code example

The same simple program written three ways: plain English, Python, and JavaScript. Notice how similar they look.

Plain English

1. Ask the user for their name
2. Save their answer
3. Print "Hello, " followed by their name

Python

name = input("What is your name? ")
print("Hello, " + name)

JavaScript

const name = prompt("What is your name?");
console.log("Hello, " + name);

All three versions do exactly the same thing: ask for a name, then say hello. Programming languages are just a more structured way to express the same instructions you'd normally write in English (or any other language).

03 · Quiz

What is code?

A secret language only experts can read
Text instructions that tell a computer what to do
A special kind of file that runs by itself
Binary 0s and 1s

04 · Fill in the blank

Code runs from top to _____, one instruction at a time.

05 · Match

Match each programming concept to its real-world analogy.

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