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Every blue dot is someone coding right now.

Right now, someone in Brazil is writing Python.

Functions01,240
Python · Lesson 42Functions

A function is a named block of code. It takes inputs and returns a result.

def add(a, b):
    return a + b
Challenge

Write greet(name) so it returns a greeting with the name in it.

main.py
1# Return a greeting for name
2def greet(name):
3 return "Hello, " + name + "!"
Test casesRun
greet("Ana")→"Hello, Ana!"
greet("Kofi")→"Hello, Kofi!"
greet("Mei")→"Hello, Mei!"
1 day streak+10

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A few lines of code. Something real.

Build a live weather site.

Make a Roblox game.

Build a parking sensor.

Build a phone app.

Learn how to talk to AI.

Ask a database.

See the math move.

Spot the fork.

And much more to explore.

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A hint, never the answer.

A few minutes a day adds up.

1day streak

Ten minutes a day.

Every lesson counts.

Level up as you learn.

Climb a new league every week.

Better with a friend.

A few missions a day.

Make it yours.

Follow a path, step by step.

Software EngineerCareer path · 7 steps
Step 1A first language, learned properly
Step 2Linux and the command line
Step 3Git and version control
Step 4SQL fundamentals
Step 5Data structures, built by hand
Step 6Algorithms and recursive thinking
Step 7Code other people can read

Free certificates along the way.

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Frequently asked questions

Is Coddy free?

Yes. Coddy is completely free to start. You can take dozens of interactive courses, build coding streaks, and earn XP without paying anything. We also offer an optional premium plan with extra features for learners who want more.

How long does it take to learn to code?

Most beginners can write useful code within 1 to 2 months of consistent daily practice. Reaching a job-ready level usually takes 6 to 12 months. Our free roadmaps for software engineering, frontend, backend and data analysis lay out that road course by course. With Coddy's gamified streaks and bite-sized lessons, you can make steady progress with as little as 15 minutes a day.

How hard is it to learn to code?

Coding is a learnable skill, not a talent. Most beginners feel lost in the first few weeks, and that's normal. The trick is short daily practice instead of long weekend sessions. Coddy's bite-sized lessons and gamified streaks are built specifically to make sticking with it easy.

Where can I learn to code for free?

Right here on Coddy. We offer free interactive courses across 20+ programming languages (Python, JavaScript, SQL, HTML, CSS, Java, C, Go, and more), taught through hands-on lessons with an in-browser code editor and Bugsy, an AI tutor that helps when you get stuck.

What programming language should I learn first?

For most beginners, Python is the easiest language to start with: it reads almost like English and is widely used in web development, data science, and AI. If web design is your goal, start with HTML, CSS, and JavaScript. Already have a job in mind? Pick a roadmap instead: it chooses the languages and their order for you. Not sure which to pick? Our short onboarding questionnaire asks a few quick questions about what you want to build and recommends the right language for you. Try it on the Get Started flow.

Can I get a certificate from Coddy?

Yes. Every course you complete on Coddy comes with a verifiable certificate. You can download it as a PDF and add it directly to your LinkedIn profile or résumé to showcase the skills you've earned.

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