HashtagAny word beginning with the # sign. People use hashtags to organize conversations around a specific topic. Clicking on a hashtag takes you to search results for that term.
MentionA public Tweet directed to another user that includes their @username. Mentions are clickable and link back to the mentioned individual’s profile.
ReplyA public response to a Tweet via the reply button. Replies show up in your home timeline and the timeline of the person to whom you are responding to. You must follow both parties to see the full conversation.
RetweetYou can pass along someone’s Tweet by retweeting it. Just hit the Retweet button to send the original message to all of your followers.
LinksTwitter’s link-shortening feature allows you to paste a link of any length into a Tweet and it will automatically be shortened.
It’s tempting to start tweeting right away. But before you begin, follow and observe brands and businesses similar to yours to see what they’re doing well. You can also search for industry keywords on Twitter for inspiration or to see what people are already saying about you.
Mention and be mentioned.
To mention others in your Tweets, include their @usernames in your message. Mention your followers in positive Tweets that contain relevant, personalized content to establish goodwill on Twitter. They may do the same for you in the future, giving you added exposure.
More about mentions and other Twitter terms