You can invite friends and members to join channels in a few different ways.
1. To begin navigate to a channel, and type '/invite' in the chat window (See below).
2. You will see a few options.
1. /invite @username
Use this to invite a specific user individually to a channel
For example: /invite @matthew.sourgoutsidis
2. /invite-all-to #room
Use this command to invite all users in a channel to join another channel
For example: /invite-all-to #the-library
3. /invite-all-from #room
Use this command in the channel you want to populate, this command allows you to all the users from a specific room or channel
For example: /invite-all-from #random
Use these commands to invite friends to channels and add group members to private conversations.