Where can I see the code of the Internet Computer?

As in other crypto networks, there are many components that make up the network.

The Replica

This repo contains many different pieces (including testing and other infrastructure components), but the most important one is the source code for the Rust implementation of the "replica" (read: "client" in some blockchains) that is compiled and run by the machines that together make up the Internet Computer: https://github.com/dfinity/ic

Important Canisters in replica repo

There are some canisters in the replica repo that are important enough that they should be highlighted.

Ledger canister

This is the canister that holds the ICP token balances: https://github.com/dfinity/ic/tree/master/rs/rosetta-api/ledger_canister

Cycles minting canister

This canister burns ICP and mints cycles: https://github.com/dfinity/ic/tree/master/rs/nns/cmc

Important canisters in the ecosystem

Internet Identity

Internet Identity is a canister that lives in the NNS. Its code is here: https://github.com/dfinity/internet-identity

Canister Smart Contract SDK

Strictly speaking, the SDK is not a part of the Internet Computer, but it is used by many developers to build dapps: https://github.com/dfinity/sdk