Oxford dictionary: (the headlines) the most important items of news in a newspaper or in a broadcast news bulletin:

The headline is THE most important piece of real estate on your LinkedIn profile!
I know everyone is trying to reach the coveted 100% completeness level for their profile, but there is another section that must command more attention.
It is often overlooked because the default setting on LinkedIn is to have your current position or title show up also as your headline. A lot of people get the headline wrong. You are not your job title, you are much more important than that.

I know some people think the summary, or specialties, or the experience is important but your headline travels with you everywhere you go on LinkedIn. Think about it, it is the only part of the profile that you can CUSTOMIZE to your specific individual information.
When you appear in search results for instance your name, location, and headline will be the three visible parts of your profile shown. Your headline shows up when you post an update, answer a question, add a skill, change a position, and on & on….. well, you get the idea, your headline shows up in 23 different areas when you travel on LinkedIn.

So make your headline a (U)nique (V)alue (P)roposition. Start with your keywords, then, if you have one, add a personal branding statement, or include how you add value, and finally target your audience.

The beginner: Consultant at Johnson and Johnson – consultant can literally mean anything.

The intermediate: Bilingual B2B Sales Professional at Edward Jones, it’s OK getting better

The expert: I use every tool in the public relations toolbox to make our clients the heroes in their own stories. This is it keywords, value, and who they solve problems for.

Knock it out of the park: Internet Marketing Expert | Looking For New Business Partnerships That Need Help With Marketing… Lets Connect! The ultimate UVP and a call to action, it’s great.

Ready, get set, (EDIT) your LinkedIn Headline, and most of all have fun with it.