Internet Computer Programming Concepts

This chapters covers Internet Computer specific features of Motoko.

It is recommended to be familiar with the following items (and their types) from the last chapter:

• functions
• records
• objects
• classes
• modules

A comparison of these concepts with actors and actor classes is available:
Motoko Items Comparison Table

Before diving in, lets briefly describe four terms that look alike, but are not the same!

• Actor An abstract notion of a self-contained software execution unit that communicates with other actors through asynchronous message passing.

• Canister An instance of an actor that runs on the Internet Computer Blockchain.

• WebAssembly Module A file containing a binary representation of a program (that may have been written in Motoko) that is installed in a canister that runs on the Internet Computer.

• Smart Contract The traditional notion of a blockchain program with roughly the same security guarantees as canisters but with limited memory and computation power.