[felixgallo]

JSON must also be serialized or deserialized. Parsing it is slow and hard and not cache friendly.

Protobuf has the benefit of being extremely compact and, in some important languages, fast and friendly to serialize and deserialize.

[MS_Buys_Upvotes]

Thanks! You and the others are right: I didn't know JSON was serialized.

I can see why something in binary would be faster than structured text (think assembler vs Python).

Thanks again.

[coldtea]

>I didn't know JSON was serialized.

Think of it like this: anytime you get stuff from the memory of your program (arrays, lists, strings, etc) and export it in a textual or binary format that can be exchanged between programs, moved over the network, saved to a file, etc, that's serialization.