Channels allow you to connect to alternate marketplaces, or channels, like eBay and Amazon. Currently there are no Channels configured. Here's a list of what's currently available. Extension Modules are available online for these Channels.
Amazon

Amazon Channel

The Amazon extension module provides functionality that adds Amazon as sales channel for your online store. Create and manage offers on Amazon, as well as retrieve and update orders. Provides realtime inventory controls, and the ability to fully manage your Amazon offerings. Alternate channel (secondary) available.

eBay

eBay Channel

The eBay extension module provides functionality that adds eBay as sales channel for your online store. Create and manage offers on eBay, as well as retrieve and update orders. Provides realtime inventory controls, and the ability to fully manage your eBay store. Alternate channel (secondary) available.

eBay

Walmart Channel

The Walmart extension module provides functionality that adds Walmart as sales channel for your online store. Create and manage offers on Walmart, as well as retrieve and update orders. Provides realtime inventory controls, and the ability to fully manage your Walmart store.