How Online Social Networks Work

By: Dave Roos
On MySpace users can connect with college friends, business acquaintances, musicians and more.
On MySpace users can connect with college friends, business acquaintances, musicians and more.
Nicholas Kamm/AFP/Getty Images

When most people hear th­e term social network, they automatically think of online social networks. That's because online social networks, also known as social-networking sites, have exploded recently in popularity. Sites like MySpace, Facebook and LinkedIn account for seven of the top 20 most visited Web sites in the world. For many users, especially the fully wired Net Generation, online social networks are not only a way to keep in touch, but a way of life.

Several features of online social networks are common to each of the more than 300 social networking sites currently in existence. The most basic feature is the ability to create and share a personal profile. This profile page typically includes a photo, some basic personal information (name, age, sex, location) and extra space for listing your favorite bands, books, TV shows, movies, hobbies and Web sites.


Most social networks on the Internet also let you post photos, music, videos and personal blogs on your profile page. But the most important feature of online social networks is the ability to find and make friends with other site members. These friends also appear as links on your profile page so visitors can easily browse your online friend network.

Each online social network has different rules and methods for searching out and contacting potential friends. MySpace is the most open. On MySpace, you're allowed to search for and contact people across the entire network, whether they're distant members of your social network or complete strangers. However, you'll only gain access to their full profile information if they agree to become your friend and join your network.

Facebook, which began as a college social network application, is much more exclusive and group-oriented. On Facebook, you can only search for people that are in one of your established "networks." Those networks could include the company you work for, the college you attended, or even your high school. But you can also join several of the thousands of smaller networks or "groups" that have been created by Facebook users, some based on real-life organizations and some that exist only in the minds of their founders.

LinkedIn, the most popular online social network for business professionals, allows you to search each and every site member, but you can only access the full profiles and contact information of your established contacts -- the people who have accepted an invitation to join your network (or have invited you to join theirs). You can, however, be introduced through your contacts to people who are two or three degrees away from you on the larger LinkedIn network. Or you can pay extra to contact any user directly through a service called InMail.

In this article, we'll talk about setting up online profiles along with how to avoid being hacked. We'll also focus on specific social networking groups from those for Information technology professions to ones geared at sneakerheads.

Check out the next page to find out how to set up social-networking profiles.

Making Connections

On social-networking sites like LinkedIn, you can choose your connections based on certain characteristics such as places you've worked on where you went to college.
On social-networking sites like LinkedIn, you can choose your connections based on certain characteristics such as places you've worked on where you went to college.
Image courtesy of LinkedIn

Before you can make an online connection, you need to create a profile on a social-networking site. You'll be asked to choose a login name and password. Once you've created those, you'll be asked for some basic personal information, such as your name, sex, age, location and any hobbies or special interests.

You can personalize your profile by adding photos, music or video files. Just remember that your profile is the image you're presenting to the online world. But on most sites you also maintain control over who can view your full profile.


On some sites, only friends or those you've invited can view your profile. When you've finished creating your profile, you can start looking for friends and making connections. You do this by inviting current offline friends to join you or by searching for friends who are already members.

Most social-networking sites include a feature where you can send an e-mail inviting friends to join the Web site and become part of your online social network. In some instances, such as on Facebook or LinkedIn, you can upload your address book from e-mail accounts such as Google or Yahoo!

After you invite your current friends, you can look for those who have similar interests. For instance, if you like to read Jane Austen books, you can look for others who like Jane Austen. You can then invite them to share your network.

Or, you can search for people who went to the same college or high school as you, people who own the same kind of car you do or those who like the same music as you. You can invite these people to join your network as well, widening your social network. For more information on social networks and how they work, check out our article on How Social Networks Work.

Even though you may feel like you know the people you meet in cyberspace, you still need to be careful. Hacking is a common occurrence. On the next page, we'll talk how you can avoid being the victim of a social-network hacker.

Hacking and Social Networks

With online social-networking sites, you have to watch for hackers who invent profiles and steal information.
With online social-networking sites, you have to watch for hackers who invent profiles and steal information.
© Chris Jackson / Getty Images

When people talk about hacking and social networks, they're not referring to the com­mon definition of hacking, which is using malicious code or backdoors in computer networks to damage systems or steal proprietary information. Hacking into social networks requires very little technical skill. It's much more of a psychological game -- using information on personal profiles to win a complete stranger's trust.

This second type of hacking is called social engineering. Social engineering uses persuasive psychological techniques to exploit the weakest link in the information security system: people [source:]. Examples of social engineering scams could be:


  • Calling a systems administrator posing as an angry executive who forgot his password and needs to access his computer immediately.
  • Posing as a bank employee and calling a customer to ask for his credit card number.
  • Pretending to lose your key card and kindly asking an employee to let you into the office.

[sources: SecurityFocus and]

When creating a profile page on a social network, many people fail to consider the possible security risks. The more personal and professional information you include on your public profile, the easier it is for a hacker to exploit that information to gain your trust.

Let's say you're an engineer and you blog about one of your current projects on your Facebook page. A hacker can use that information to pose as an employee from that company. He has your name and your position in the company, so you're liable to trust him. Now he can try to get a password out of you or proprietary information that he can sell to your competitors.

The security advantage of most online social networks is that only your "friends" or members of your network can see your complete profile. That's only effective if you're extremely selective about whom you include in your network. If you accept invitations from absolutely everyone, one of those people may potentially be a hacker.

The problem with online social networks is that they have no built-in authentication system to verify that someone is indeed who they say they are [source:]. A hacker can create a free profile on a site like LinkedIn, designing his profile to match perfectly with the business interests of his target. If the target accepts the hacker as a connection, then the hacker suddenly has access to information on all of the target's other connections. With all that information, it's possible to construct an elaborate identity theft scam.

To fight back against social engineering, the key is awareness [source:]. If you know that social engineering hackers exist, you'll be more careful about what you post on your online profiles. And if you're familiar with common social engineering scams, you'll recognize a con when it's happening instead of when it's too late.

On the next page, we'll talk about social-networking sites for information technology professionals.

Information Technology Social Networks

Internet professionals rely on social-networking sites to communicate with other IT professionals and to network.
Internet professionals rely on social-networking sites to communicate with other IT professionals and to network.
© Photographer: Rosmizan Abu Seman | Agency: Dreamstime

Information technology professionals and amateur geeks have been gathering online since Usenet fi­rst launched in 1979. For people who spend their workday in front of a computer facing new technology challenges, it's natural that IT professionals took quickly to online forums, newsgroups and discussion boards. IT social networks are the latest extension of these virtual communities.

IT Toolbox is a global information technology social network with more than a million members. Following the standard model of online social networks, members of IT Toolbox can create user profiles with personal information, professional experience, a profile photo and even a blog.


IT Toolbox members can search out colleagues and new contacts in their profession and invite them to become a connection. These connections then show up as links on the member's profile page.

However, the majority of the action on  information technology social networks still takes place on the message boards. IT Toolbox allows members to form groups to discuss the latest topics in their fields. Or users can add tips and ask questions on special "knowledgebase" pages dedicated to topics like networking or Java. The site also hosts an IT Wiki open to submissions and edits from members.

Job postings are an important part of any information technology social network. Information technology is one of the fastest-growing job sectors in the US economy (network systems analyst is the #2 fastest-growing job after home health aide) [source: Career OneStop]. Employers looking for top talent will not only post jobs on information technology social networks, but browse for qualified members to poach from other companies.

There exist many other social networks that don't have as much functionality as a site like IT Toolbox, but are still important gathering places for the tech community. Slashdot is a tech news site that's been drawing an avid membership since 1997. And Digg, one of the most popular social bookmarking sites, has a decidedly tech news bent as well.

On the next page, we'll talk about social-networking sites for adults.

Social Networks for Adults

Image courtesy of Sermo Physicians can network and exchange information on Sermo.
Image courtesy of Sermo Physicians can network and exchange information on Sermo.
Image courtesy of Sermo

Whil­e adults have joined online social networks that have been previously dominated by teens like MySpace and Facebook, adult users are also joining online social networks targeted at adult members. Adult social networks don't specialize in "adult" content (although those certainly exist), instead they're social networks for professionals rather than purely for friends.

With over 15 million members, LinkedIn is the largest online social network for business professionals. On LinkedIn, profile pages read more like resumes, citing professional experience and education and leaving out personal tidbits like favorite books and bands. Not until recently did LinkedIn even allow users to post a profile picture for fear that it would turn the strictly business site into yet another excuse for online dating.


LinkedIn users can leverage existing contacts and relationships to find new jobs and partnerships. On LinkedIn, for example, you can search for job postings within your network. If it turns out that your best friend went to college with the guy who's hiring, that could give you a significant advantage over other applicants.

Professional recruiters are also tapping into the tremendous professional databases on sites like LinkedIn. Recruiters can pay extra for LinkedIn Corporate Services, a service that allows them to run targeted searches for members who meet their experience and location criteria. The advantage of a service like LinkedIn is that recruiters can zero in on "passive applicants," professionals who are highly qualified but not necessarily looking for a new job. These people are considered more attractive to employers since they've proven their ability enough to hold down a job.

Several adult social networks cater to specific professions. According to an article in the Wall Street Journal, doctors are meeting up on a physician's social networking site called Sermo and advertising, marketing and media execs are sharing tips and tricks on another social network called AdGabber [source: Wall Street Journal].

On the next page, we'll talk about social networks for sneaker enthusiasts.

Sneaker Culture Social Networks

Sneaker fans can share opinions on limited-edition shoes such as these from Nike.
Sneaker fans can share opinions on limited-edition shoes such as these from Nike.
© Gareth Cattermole / Getty Images for Nike

Sneaker culture social networks are Web sites where sneaker collectors -- a.k.a "sneakerheads" -- gather to compare collections (200 pairs isn't rare), post pics of their favorite customized "kicks" and keep posted on the newest releases from the hottest brands.

Ever since Run-DMC rapped about "My Adidas" back in 1986, sneakers have been inextricably tied to hip-hop culture. A year earlier, Nike released its first pair of Air Jordans, linking the world's best-known athlete with what would come to be the world's most coveted shoe (an original $65 pair of Air Jordan recently sold on eBay for over $2,000) [source: ']Time].


Between the cult followings that formed around Adidas and Nike in the 1980s, athletic shoes went from being practical accessories to fashion statements and even political statements. Run-DMC's lace-less white Adidas, for example, not only looked cool, but were a nod to prison culture, where laces were often confiscated [source: YouTube].

Sneakerplay is the largest and most active sneaker culture social network online. Members can create MySpace-like profile pages with embedded MP3 music files, blogs, and of course, plenty of pictures of their sneaker collections. There's even a section on the site for sneaker battles, where visitors to the site vote between two pairs of prized footwear.

Sneaker culture is fueled by an obsession with limited-edition releases and rare retro shoes. Nike keeps the craziness alive by releasing extremely limited editions that are only sold in one store, one day, and that's it.

For example, Nike manufactured just 140 pairs of its Cowboy Air Max 180s and sold them at a single store in Miami [source: Time]. People have been known to camp out for days to get their hands on these rarities. Some simply add the sought-after shoes to their collections, while others turn around and sell them online for huge profits.

On the next page, we'll talk about social networking groups for fashionistas.

Fashion Social Networks

StyleHive is a social network that allows members to share thoughts on fashion.
StyleHive is a social network that allows members to share thoughts on fashion.
Image courtesy of StyleHive

Fashion social networks are Web sites where members post pictures of their latest looks, share opinions on fashion trends, join virtual fashion groups and make friends with budding fashionistas from around the world. Fashion social networks ­can be standalone sites like Share Your Look or StyleHive or exist as a niche within a larger social networking site like MySpace Fashion.

Fashion social networks are an online retailer's dream come true. According to Internet traffic analysts at ComScore, the more time people spend on social networks, the more likely they are to shop at online stores for clothing, music, luxury items and electronics. Of the 61.2 million people who visited online retailers in August 2007, nearly 25 percent were labeled "heavy" social network users [source: Clickz].


ComScore found an especially lucrative connection between online clothing retailers and heavy social network users. Over half of the August 2007 visitors to brand name sites like Alloy and Hollister were heavy social network users [source: ComScore].

A fashion social networking site like FashMatch is meant to capitalize on the strong correlation between social network users and online shoppers. On FashMatch, members can choose tops, bottoms, dresses, shoes and accessories from dozens of brand-name retailers and create their own match (outfit) to share with other members. Members rank each other's matches, collect fans (friends) and proudly advertise their favorite brands. It's word-of-mouth marketing at its finest, with links to buy!

Other fashion social networking sites, like the Australian-focused Fashionising are geared more toward fashion professionals. Visitors to Fashionising can register as a designer, model, stylist, photographer, etc. Another site, ModelsHotel is a highly exclusive fashion social network just for models.

Some common features of fashion social networks are the ability to organize looks by recent posts, most viewed, highest ranked, etc. Most allow you to search for styles using tags like "black," "shirt," "sexy" and so on. All of them allow you to search out and make friends with other users, becoming a "fan" or "follower" of someone else's fashion ideas. Many include wishlists for items that members would love to have in their closet and even the ability to post styles on social bookmarking sites like Digg and

For lots more information about social networks and related topics, check out the links on the next page.