A blockchain, or a chain is defined by a Virtual Machine (VM) and a set of validators (subnet). Three chains are available at launch:
P-Chain: "platform chain", it manages the Avalanche network;
C-Chain: "contract chain", an Ethereum-like blockchain for smart contracts;
X-Chain: "exchange chain" default chain for asset transfers.
Every main chain has a characteristic color that lets users understand how assets move between chains. You can search any chain by:
Entering the chainID in the search bar;
Clicking on the ALL BLOCKCHAINS link in the navbar;
Click on the BLOCKCHAINS box in the left column at the center of the home page.
The last two options will bring you to the complete list of the blockchains deployed on the network.
By default, Avascan shows all chains validated by the Default Subnet, but clicking on the Change button will show a list of all available subnets, filtering the list of blockchains by the subnet that validates them. To show only the blockchains validated by the Default Subnet, click on the Show Default Subnet button.
To enter the Blockchains Details page, simply click on a list item. The Blockchain Details page shows:
Blockchain ID (except P-Chain);
Status of indexing on Avascan (i.e. if you can search assets, addresses transactions and/or smart contracts on it);
The related Subnet, along with subnet ID and total number of validators.