On Facebook, you can show interest in your friends' updates by commenting on or liking the content they've shared. Take a look at your news Feed and ticker, and pick out an update that you wish to respond to. You can publicly endorse a post by clicking the Like button below it. To undo this action, click the Unlike link. To add a comment, click into the comment box below the update, type your comment and hit "enter." If you'd like to create a new paragraph within your comment, press "Ctrl + Enter." You will be notified when others add comments to this story. You can repost videos or links to share with your own network by clicking the "Share" link below a post. With the dropdown at the top, choose where you want to post the link, then add a comment to accompany the link in the box below if you'd like. If you'd like to remove the original poster from your link click "Remove" next to their name. Click the "Share" button when you're ready to post your link. If you'd like to be notified when a post receives likes or comments, click the down arrow to the right and select "Follow Post."