Types of TweetDeck columns and what they display:
- Home: Timeline for one of your accounts
 - Search: A column for a specific search term
 - Followers: Follow activity for all your accounts or one specific account
 - Tweets: Tweets from a specific account
 - Mentions : Only includes when users mention a specific account
 - Messages: Direct messages for a specific account
 - Mentions (All Accounts): Only includes when users mention a specific account
 - Messages (All Accounts): Direct messages for a specific account
 - Activity: What’s happening with the accounts you follow
 - Inbox: Direct messages from all your authorized accounts in aggregate
 - User:
 - Favorites: Tweets marked as favorites from a specific account
 - Trending: A column dedicated to specific worldwide trends
 - Lists: Assign or create a list to be displayed within a column
 - Collection:s A timeline of curated Tweets, hand-selected by you, that you can share with others
 - Scheduled: Your scheduled Tweets
 
https://support.twitter.com/articles/20169914-tweetdeck-columns#
