LinkedIn can be a useful tool for finding a new job or for making long-term career plans. But in order to take full advantage of all that the social network can offer, you should invest some time in getting to know the site. You’ll want to make sure your profile and job title are updated, and that you know about all of the platform’s features.

Whether you are a job-seeker or a recruiter, LinkedIn has much more to offer its members than just a system of cataloging business connections. Here are three features that you might not have known about that can turn you from a casual LinkedIn user into a business powerhouse.

1. Skills and Expertise Searches

Under the “More” tab at the top of the site, you’ll find a link for “Skills and Expertise.” This feature is designed to help members see where their abilities fit into the grand scheme of LinkedIn’s more than 100 million members, and to get inspiration for further professional development.

For example, a search for Twitter in this feature yields a long list of related areas of expertise. It also shows businesses related to the platform and some of the top professionals who list Twitter on their profiles. You can also see demographic information about the subject, with a chart showing the ages of Twitter professionals, the number of people listing the network as a skill, and the relative growth of Twitter as an expertise.

This feature can give you some insight into the situation of your particular skills in the broader business world, as well as providing some ideas for other topics that could be helpful. You can add skills directly to your profile through this feature, and it also has a button called “See Suggested Skill” that offers personalized recommendations. You can see skills similar to the ones already on your profile, as well as the number of members who list the expertise and how much that number has changed over the past year.

2. Third-Party Apps

LinkedIn has a large suite of internal and third-party apps to expand the capabilities of the basic platform. For example, its acquisition of SlideShare means that members can use the SlideShare Presentations app to include presentations and videos on their profiles. This can make your profile more unique and can make it easier to showcase your past work.

Other third-party options include apps from file-sharing site Box.net and project-management platform Manymoon; these apps can really help boost your productivity on LinkedIn. Other apps focus on building the social connections needed for good business. Using the Cardmunch app, you can take a photo of a business card and automatically convert it into a contact on LinkedIn. It cuts down on the paper trail and the possible human error of losing a card at a big networking event. Another app that emphasizes social interaction is LunchMeet. Sign in with LinkedIn and post your location and lunchtime availability, then look for other users who you might want to grab a bite with.

3. Premium Account Features

If you’re a serious LinkedIn member, upgrading to a premium account opens up several additional features that help you build connections. One of the most useful is the Profile Organizer. This helps you manage profiles and connections by sorting them into folders. You can also add contact information and notes about each profile. Different accounts grant you different numbers of folders, so an Executive-level member can sort contacts into 50 folders.

Other features allow paid members to receive messages from any other person on the network through OpenLink, which makes you available for communication without sharing your contact information. You can also make requests for introductions within companies you are targeting. It can also make your searching more precise with advanced filters. These premium features can make recruiting, in particular, an easier task.

Have you tried out any of these features? Know of any other lesser known LinkedIn features that pack a punch? Let us know in the comments!

[Image credits: Sheila Scarborough, John LesterLee Haywood]