Use @mentions to notify others of your posts, and use #hashtags to make it easier to search and filter your posts.
An @mention is a method of notifying colleagues of your post. An @mention contains @username anywhere in the body of the post. Use the @mentions feature to mention specific colleagues and share your news with them. The users that you mention are notified of your post, even if they are not following you. You can use @mentions anywhere in the product.
This feature encourages other people to respond to your update and can result in a more engaging conversation.
If you include more than one @mention in your post, all those people see the post in their @Mentions filter. Make sure that you separate @mention entries with a space. For example, @JohnSmith, @MaryJones. When you start typing a username, the type-ahead feature provides available choices from the directory.
@Mentions that specify your @username are collected and are displayed in the @Mentions filter on your Homepage. You can only view @mentions that specify your @username.
A #hashtag is any word or phrase with the number (#) sign immediately preceding it. The # sign converts the word into a link that makes it easy to find and follow a conversation about that topic. You can use #hashtags in status updates and in comments about status updates.