About social networks and blogs
Social networking sites are a way of using your computer, tablet or smartphone to connect with other people - to share views, news, knowledge and ideas, and also to build friendships.
Most sites are easy to sign up to, and they're usually free.
You can also connect with people by writing or responding to a 'blog' - which is an online personal diary with thoughts and opinions on different aspects of life.
Social networking sites and blogs are available 24-hours a day and allow you to interact with people all over the world.
Facebook and Twitter
The two most popular social networking sites are Facebook and Twitter.
Twitter allows users to post short comments called 'tweets' - which other people can respond to and share. Many people, including celebrities and politicians, post their updates on public accounts.
When you 'follow' someone on Twitter, you will see their comments when you log in to your account. Similarly, anyone 'following' your account will be able to see what you've tweeted.
If you join Facebook, you create a profile page which is a bit like a noticeboard. This is where you can share updates - including news, photos and stories - with family, friends and colleagues.
Facebook also has other features. For instance, you can play games with your friends across the internet, join groups of people with similar interests, and interact with topical Facebook pages about people, things or places. These pages could be about anything - from your favourite TV show to your preferred brand of coffee.
Using privacy settings on a social networking site will restrict access to your profile and prevent strangers finding out personal information about you.
Anyone can sign up to a social network. Inevitably, sites attract a small minority of users who want to promote extreme views or cause trouble. It's therefore important to take precautions.
Be careful who you allow to join your network and who you disclose personal information to. Avoid revealing private details such as your address, phone numbers and date of birth.
Social networking sites usually allow you to send private messages to people you're connected to. It's always worth considering using this option rather than revealing too much personal information on a publicly-visible page.
Social networking site Google+ lets you arrange all your online contacts in separate 'circles', so you can share something with your best friends that you might not want to be seen by your work colleagues.
Pinterest encourages users to share ideas on a variety of topics (such as travel, food, fashion and arts & crafts). You 'pin' images, videos and other objects of interest onto virtual pinboards.
Other networks, such as LinkedIn, are designed to help people connect with work colleagues or business contacts - which can be useful when you're looking for a new job or need professional advice.
Social networking sites also let you search for people you know. And because other people can search for you in return, you may end up reunited with a long-lost classmate or colleague!
Some people enjoying interacting with others on blogs - these are online journals where stories or subjects can be shared with readers over weeks, months or years. Popular blogging services include Tumblr, WordPress and Blogger.
If you find yourself reading a blog you really enjoy, you can add comments and questions at the end of a story. In fact, most authors want readers to respond.
And, if you're inspired, you could start your own blog and share your experiences or passions with the rest of the world.
Bear in mind that once you post something online, you can't always take it back. Don't post comments, photos or videos that may cause embarrassment, and never post comments that are abusive or may cause offence.
Think about your reputation first. People have lost job opportunities, been sacked, sued or even, in rare cases, jailed because of posts they made on social networks.
You can find out more about how to safely connect and interact with people on social networking sites by taking a look at the links below.