What is Wi-Fi?

Privacy, Devices & Citizenship · lesson 5 of 17 · 15 min

What is Wi-Fi?

Wi-Fi is a way for your device to connect to the internet without using a physical cable. It uses invisible radio waves — similar to how a radio picks up music from a station — to send and receive information through the air. These radio waves travel at very high speeds, which is why you can load a webpage or watch a video almost instantly.

A device called a router in your home or school creates the Wi-Fi signal. When your device connects to the router, it can access the internet. The router is connected to the internet through a cable from your internet service provider (ISP) — the company that provides your internet connection.

Wi-Fi is incredibly convenient, but not all Wi-Fi networks are equally safe. The security of a Wi-Fi connection depends on whether it is protected by a password and how strong that protection is.

Safe vs. unsafe Wi-Fi: Your home Wi-Fi is protected by a password — only people who know the password can use it. Public Wi-Fi (at a café, library, or airport) is open to everyone, which makes it much less safe. Avoid entering passwords or personal information on public Wi-Fi.

Home Wi-Fi vs. public Wi-Fi

🏠 Home Wi-Fi — safer

  • Protected by a password
  • Only trusted people in your home can connect
  • Encrypted — data is scrambled so others cannot read it
  • You control who has the password

☕ Public Wi-Fi — riskier

  • Open to anyone — no password required
  • Strangers on the same network could see your activity
  • Avoid logging into accounts or entering personal information
  • Fake “free Wi-Fi” hotspots can be set up by scammers

Wi-Fi safety tips

  • Only connect to Wi-Fi networks you recognize and trust.
  • Never share your home Wi-Fi password with people outside your family without a trusted adult’s permission.
  • On public Wi-Fi, avoid logging into accounts or entering personal information.
  • If a Wi-Fi network asks for personal information to connect, tell a trusted adult — this is a red flag.
  • Look for the padlock icon in your browser — it means the website is using encryption to protect your data.

Key words to remember

  • Wi-Fi
  • Router
  • Public Wi-Fi
  • Encryption
  • ISP

Match each Wi-Fi concept to its description

Wi-Fi safety — quiz

How does Wi-Fi connect your device to the internet?

  • Through a cable plugged into your device
  • Using invisible radio waves through the air
  • By using your phone’s battery
  • Through a satellite in space

Answer: Using invisible radio waves through the air
Wi-Fi uses radio waves to send and receive information wirelessly.

Why is public Wi-Fi less safe than your home Wi-Fi?

  • It is slower
  • It uses more battery
  • Anyone can connect to it, not just trusted people
  • It only works on phones

Answer: Anyone can connect to it, not just trusted people
Public Wi-Fi has no password, so anyone — including bad actors — can connect and potentially see your activity.

It is safe to enter your passwords on public Wi-Fi at a café.

  • True
  • False

Answer: False
Public Wi-Fi is not secure. Avoid entering passwords or personal information when connected to it.

What is a router?

  • A type of computer virus
  • A device that creates a Wi-Fi signal and connects devices to the internet
  • A type of password
  • A cable that connects to the internet

Answer: A device that creates a Wi-Fi signal and connects devices to the internet
A router creates the Wi-Fi signal in your home or school and connects your devices to the internet.

What should you do if a Wi-Fi network asks for personal information to connect?

  • Enter your information — it is probably safe
  • Tell a trusted adult — this is a red flag
  • Connect anyway and ignore the request
  • Share the network with friends

Answer: Tell a trusted adult — this is a red flag
Legitimate Wi-Fi networks do not ask for personal information to connect. This is a warning sign.

You should share your home Wi-Fi password with anyone who asks.

  • True
  • False

Answer: False
Only share your home Wi-Fi password with trusted people, and always ask a trusted adult first.

What does encryption do?

  • Makes your internet faster
  • Scrambles data so others cannot read it
  • Connects you to more Wi-Fi networks
  • Saves your passwords

Answer: Scrambles data so others cannot read it
Encryption scrambles your data so that only the intended recipient can read it — protecting your information.

What does the padlock icon in your browser mean?

  • The website is blocked
  • The website is using encryption to protect your data
  • The website is slow
  • The website requires a password

Answer: The website is using encryption to protect your data
The padlock icon means the website is using HTTPS encryption — your data is protected in transit.

Which of these is the safest Wi-Fi to use?

  • Free public Wi-Fi at a café
  • Your home Wi-Fi with a strong password
  • A Wi-Fi network with no password
  • Any Wi-Fi that is fast

Answer: Your home Wi-Fi with a strong password
Home Wi-Fi with a strong password is the safest — only trusted people can connect.

A scammer could set up a fake “free Wi-Fi” hotspot to steal your information.

  • True
  • False

Answer: True
Fake Wi-Fi hotspots are a real threat — always verify a network is legitimate before connecting.


Previous lesson: What is a computer?
Back to Privacy, Devices & Citizenship
Next lesson: What is a network?