Wirebook

How does the internet actually work?

Short, hands-on lessons that explain the web in plain words, with real things to poke at. Everything runs on a single small server you can watch in real time.

Start with lesson 1 Can a website get tired?

Lessons

  1. 1 What happens when you open a web page?Follow one click from your keyboard to a server and back: DNS, the padlock handshake, HTTP, tunnels and painting the page.6 min · interactive
  2. 2 Anatomy of a web addressPaste any web address and see it taken apart, colour by colour: scheme, host, port, path, query and the fragment that never reaches the server.5 min · interactive
  3. 3 Can a website get tired?Why websites slow down or fall over when too many people visit at once.7 min · interactive
  4. 4 Secret codes: encryption and hashingFrom Caesar's cipher to the AES-256 lock behind every padlock: encrypt and decrypt in your browser, crack a code by brute force, and watch one letter change a SHA-256 fingerprint completely..7 min · interactive
  5. 5 What do 404 and friends mean?The three-digit codes behind every web page, explained: 200, 301, 404, 429, 500 and the 418 teapot.5 min · interactive
  6. 6 How does a message cross the world in a blink?Race an undersea cable against satellites between any two cities, see why glass threads on the sea floor carry almost all the world's data, and chop a message into packets that arrive in a jumble..7 min · interactive
  7. 7 Why does Wi-Fi get weaker through walls?Build a little house, drag the router around and watch the Wi-Fi signal spread room by room.7 min · interactive
  8. 8 Where do deleted files and photos go?Delete a photo, empty the bin, and watch what really happens on a pretend disk: the file is forgotten, not rubbed out.7 min · interactive
  9. 9 How does a map know where you are?Find a hidden phone using nothing but satellite clocks: listen to each satellite, draw its ring and watch the rings meet.7 min · interactive
  10. 10 How does a video app guess what you'll watch next?Be the viewer a pretend video app learns about: watch, skip and say not interested, then see its notebook, your taste twins and why every video was picked.7 min · interactive
  11. 11 How does face unlock know it's you?Design a face, set up a pretend face unlock and see who gets in: you in glasses, your twin, a stranger, a printed photo.7 min · interactive
  12. 12 How does a game remember where you got to?Play a tiny game, switch the pretend tablet off and see what survives: working memory (RAM) versus the storage drawer, autosave checkpoints, a battery dying mid-save, checksums and cloud saves.6 min · interactive
  13. 13 How does a game know you really won?Play a 10-second star-catch game, then try to fool the high-score server: change the message your tablet sends, fake every move, build a wobbly bot.6 min · interactive
  14. 14 How can lots of people play the same game together?Share a pretend park with friends in other houses: every move is a message to a shared world on a server.7 min · interactive
  15. 15 How does a website check your password without keeping it?Make up a password, store it on three pretend websites (plain text, a plain fingerprint, salted and slow), then let a thief steal all three.8 min · interactive
  16. 16 How can you spot a fake message?Sort a pretend inbox of real and sneaky fake messages from games, banks, parcels and friends.7 min · interactive
  17. 17 What are bots doing on the web?Be a crawler robot on a tiny pretend web: read each site's robots.txt sign, follow links, build a search index and see what happens if you ignore the rules or rush.7 min · interactive
  18. 18 What is a cookie on a website?Fill a pretend browser's cookie jar: see how a website remembers your basket and login, what session cookies are and what closing the browser throws away.7 min · interactive

Bonus lessons

  1. ★ Why do phones and computers get hot?Heat up a pretend phone with games, charging, a duvet or a sunny car, tug a pretend blanket to feel how insulation traps heat, and watch it slow down to protect itself.Bonus · 9 min · interactive
  2. ★ Why do emojis turn into boxes, question marks or gibberish?X-ray any emoji to see the secret numbers and bytes inside it, solve four crime scenes where emojis seem to vanish (empty boxes, ?, mojibake and broken families) and glue your own emoji together.Bonus · 6 min · interactive
  3. ★ Why can two passwords look the same but only one works?Drag a magnifying glass over a pretend message to reveal glowing ghost footprints left by invisible Unicode characters, read a plain-words card for what each blank does, paste any text into an X-ray, repair broken messages while keeping ordinary spaces, and solve three cases where a password, filename or file looked identical but wasn't..Bonus · 7 min · interactive
  4. ★ Why does a video call go blurry when the connection is slow?Dial a pretend video call's bandwidth thinner, spend a tiny 10-bit budget on eyes vs mouth vs wallpaper to still read a facial expression, then reveal the clear face.Bonus · 7 min · interactive
  5. ★ Why can a download pick up where it left off?Break a pretend file into numbered pieces, interrupt the download, and compare restart-from-zero with resume-using-byte-ranges.Bonus · 6 min · interactive
  6. ★ Who stole all the emojis?Interview four suspects in a Byte Bakery chat heist, X-ray the fake paw prints, and discover how autocorrect and a spam cleaner teamed up to frame the cat.Bonus · 7 min · interactive
  7. ★ Why does the website still show the old picture?Compare the logo on a pretend server with the copy on your browser shelf.Bonus · 6 min · interactive
  8. ★ How can two people draw on the same picture at once?Colour one picture on two pretend tablets, switch their Wi-Fi off and on, and compare three rules: last save wins, take turns, and merge square by square.Bonus · 6 min · interactive
  9. ★ Where did my day off go?Christmas 2027 lands on a weekend.Bonus · 8 min · interactive
  10. ★ I changed who can open my link. Does the old link still work?Check a picture and its audience before you share it, then be the guard at the door: pretend visitors with badges and forwarded links, a fresh check on every visit, badges taken away, a link replaced, and a saved copy that no website can snatch back.Bonus · 7 min · interactive
  11. ★ Does the app keep peeking, or does the website ring a doorbell?How does a news app know a new lesson appeared? Race a peeker, a messenger who waits at the door and a doorbell through a pretend day, count the wasted trips, be the peeker yourself, and peek at this site's real feed to see a 304 Not Modified.Bonus · 6 min · interactive
  12. ★ Can a sticker change where a QR code takes you?Build a QR code and colour its parts (corner finder squares, timing lines, alignment square, format notes, message), scratch it, tear it and stick a price label on it while a real decoder tries to read it at four levels of spare data, then be the sticker detective: preview where five pretend posters really go, compare with the printed address and spot the fake.Bonus · 8 min · interactive
  13. ★ How does the router know which device asked?Your home has one internet address but lots of screens.Bonus · 7 min · interactive
  14. ★ Can a blocky picture be made sharp again?Guess a mystery blob made of just 16 squares, buy back real patches of detail with five coins, then see the original.Bonus · 7 min · interactive
  15. ★ Why does the video call freeze when you walk to the kitchen?A phone holds one Wi-Fi box's baton at a time, and the phone decides when to pass it on.Bonus · 7 min · interactive
  16. ★ Why does a video go blurry, then sharp?You press play and the picture is smudgy for a second, then it snaps sharp.Bonus · 8 min · interactive
  17. ★ Why does a full battery die in the cold?Your tablet said 45% and switched off on a snowy hill, then came back indoors.Bonus · 7 min · interactive
  18. ★ Why does the game lag when someone starts a download?Your internet line is a shop with one checkout and a download is a shopper with endless trolleys.Bonus · 9 min · interactive
  19. ★ Why does zipping photos barely make them smaller?Guess which four suitcase items will squash — a repeating chorus, a letter, a camera photo and TV snow — then pack them with a real (tiny) compressor and see.Bonus · 7 min · interactive
  20. ★ How does a phone know a song from hearing it?Hold up a phone in a noisy shop and it names the song in seconds.Bonus · 8 min · interactive
  21. ★ How does a TV remote work when nothing comes out of it?Press a pretend remote and see the invisible infrared flashes it sends: a wake-up flash, 32 bursts with long and short gaps, and a 38,000-a-second flicker that stops sunshine fooling the TV.Bonus · 8 min · interactive
  22. ★ How does a photo fly to the phone next to you?Send a pretend photo to the phone next to you and watch how AirDrop and Quick Share really work: a tiny Bluetooth shout to find each other, a private Wi-Fi lane with no router, and numbered pieces that fly over like paper aeroplanes and click back together like a jigsaw.Bonus · 8 min · interactive
  23. ★ What happens when you squish a video too much?Squish a real (tiny) picture the way phones squish video: watch thin whiskers crumble first, then 8x8 blocks appear, then a splat.Bonus · 10 min · interactive
  24. ★ Why is copying to a USB stick so slow?Send ants carrying crumbs from a laptop, over a bridge, into a USB stick and watch what really slows a copy down: a skinny USB 2 bridge, tired ants when the fast cache runs out, or paperwork for thousands of tiny files.Bonus · 10 min · interactive
  25. ★ How does a text message find its way to someone's phone?Send a pretend text as a frog: it hops by radio onto a lily pad (a phone tower), rides underground pipes to the message centre, which looks up where your friend's phone is, then hops off the lily pad next to them.Bonus · 8 min · interactive
  26. ★ Is my hard drive getting old? Reading its health chartTake Grandpa Spinner (a spinning hard drive) and Granny Chip (an SSD) for a check-up: change the readings on their SMART health chart, patched spots, wobbly spots, a crackly cable, temperature, age, writing life and spare pages, and hear what they tell you, from fit as a fiddle to stop using it now.Bonus · 8 min · interactive
  27. ★ How does a game controller talk to a console?Your controller fires tiny paper darts at the console hundreds of times a second, each one a snapshot of every button and stick.Bonus · 8 min · interactive
  28. ★ Why does the internet slow down in the evening?Picture the internet as water: your house's pipe, one shared pipe under the street and a big main from far away.Bonus · 9 min · interactive
  29. ★ Why does every speed test give a different answer?A speed test is a water-balloon race: fill a balloon from the internet tap for ten seconds and divide the water by the time.Bonus · 9 min · interactive
  30. ★ Why does a game judder when it can't keep up?A screen is a flip book with a thumb that turns the page on a steady beat, and the game is an artist drawing the pages.Bonus · 9 min · interactive
  31. ★ Why does the TV say "No signal"?Before any picture appears, a console and a TV shake hands: the TV says hello, hands over a menu card of every picture it can show, the console picks the best one on both lists, and for films they swap a secret password.Bonus · 9 min · interactive

🔍 The Big Case: who took the cookie jar?

Every lesson reveals one piece of a secret picture. Then use your detective skills on five clues to find who raided the Byte Bakery. Anyone can play.

Open the case file

Your stamp book

Pass a lesson's quick quiz to collect its stamp. Every stamp also sticks a sticker on your detective hat and moves you up a rank, from Curious Visitor to Chief Inspector, and reveals a piece of the Big Case picture. Stamps are saved only in this browser (local storage). We never see them.

Your detective hat, with a sticker for every stamp 🖱️🔗😴🔐🫖🌍📶🗑️🛰️📺🙂💾🏆🎮🔑🎣🤖🍪

Detective rank

Curious Visitor

  1. Curious Visitor0 stamps
  2. Rookie Detective1 stamp
  3. Junior Detective3 stamps
  4. Inspector6 stamps
  5. Chief Inspector18 stamps

Collect all 18 stamps to win the golden magnifying glass. It shows up in the deleted-files lesson.

Make a detective card to save or share

Drawn in your browser. Your name (optional) is never sent anywhere.

  1. 1The journey of a click
  2. 2Reading a URL
  3. 3Busy servers & queues
  4. 4Locks & fingerprints
  5. 5Status codes
  6. 6Across the world
  7. 7Wi-Fi through walls
  8. 8Deleted files
  9. 9Maps & GPS
  10. 10Recommendations
  11. 11Face unlock
  12. 12Saving games
  13. 13High scores & cheats
  14. 14Playing together
  15. 15Passwords
  16. 16Spotting fakes
  17. 17Bots & crawlers
  18. 18Cookies

Why this exists

The web is the biggest machine people have ever built, and almost nobody gets shown how it works. These lessons use real requests to a real server, so what you see isn't a cartoon: it's exactly what happens every time you open a page.