WebSocket for live updates in Raspberry Pi - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a WebSocket?

A WebSocket is a way for a computer to keep a connection open with a server so they can send messages back and forth instantly, like a phone call instead of sending letters.

beginner

Why use WebSocket for live updates on a Raspberry Pi?

WebSocket lets the Raspberry Pi get new information right away without asking again and again, saving power and making updates faster.

intermediate

Which protocol does WebSocket use to start a connection?

WebSocket starts with an HTTP handshake, then switches to the WebSocket protocol for continuous communication.

intermediate

How does a Raspberry Pi listen for WebSocket messages in Python?

It uses a WebSocket client library to connect and then waits for messages in a loop, reacting when new data arrives.

beginner

What is a common use case of WebSocket on Raspberry Pi?

To show live sensor data or control devices instantly from a web page without refreshing the page.

What makes WebSocket different from regular HTTP requests?

A It requires no internet connection.

B It sends data only once and closes immediately.

C It keeps the connection open for instant two-way communication.

D It uses email to send messages.

WebSocket keeps the connection open so both sides can send messages anytime without reconnecting.

Which language is commonly used on Raspberry Pi to handle WebSocket connections?

A HTML

B Python

C CSS

D SQL

Python is popular on Raspberry Pi for programming WebSocket clients and servers.

What is the first step in establishing a WebSocket connection?

A Sending a text message

B Running a SQL query

C Closing the connection

D HTTP handshake

WebSocket starts with an HTTP handshake to upgrade the connection.

Why is WebSocket good for live updates?

A Because it sends updates instantly without waiting.

B Because it stores data in a database.

C Because it uses less electricity than a light bulb.

D Because it only works offline.

WebSocket sends data instantly as soon as it is available.

Which of these is NOT a feature of WebSocket?

A Automatically saves data to disk

B Continuous connection

C Two-way communication

D Instant message delivery

WebSocket does not save data to disk automatically; it only manages communication.

Explain how WebSocket helps a Raspberry Pi show live sensor data on a web page.

Think about how the Pi and browser talk without waiting.

Describe the steps to set up a WebSocket client on a Raspberry Pi using Python.

Focus on the code flow from start to receiving data.