What is JSON? Edit it live and see why APIs are so strict about it

When an app asks a server for data, the reply has to travel as plain text. JSON is the format most web APIs use: six kinds of value, written with strict rules, that nearly every language can read and write.

Edit a live JSON text in your browser, trigger the classic mistakes (single quotes, trailing commas, missing commas) and see exactly where the parser stops. Then learn what gets lost when you turn data into JSON and back.