Tweets are visible to everyone or visible by default. But tweeters can restrict message delivery to just their followers. You can tweet from your smartphones or by SMS available in certain countries. Users may Subscribe to other users tweets--- this is following. And Subscribers are known as followers or tweeps (twitter+peeps=tweeps) Twitter allows users the ability to update their profile by users their phone. Users may subscribe to other users' tweets – this is known as following and subscribers are known as followers. The users can also check the people who are un-subscribing them on Twitter better known as unfollowing via various services. Twitter allows users the ability to update their profile by using their mobile phone either by text messaging or by apps released for certain smartphones and tablets.
As a Social Network, Twitter revolves around followers, when following someone or 20 people and mixture of the tweets pop up on your newsfeed. Users are only able to send and readtext-based messages of up to 140 Characters known as "tweets." When making Tweets, you can put anything you want. Either about a famous star, to sports to anything you want. And if your intresting enough you might get some followers!