There has been ongoing debate about what information to include in your LinkedIn profile ever since the platform launched. If you're job searching, here's my take on it.
If you want to impress recruiters so they will contact you for an interview, you're going to make your resume as good as it can possibly be, right? Yes, you can also impress them with your communication skills, what you write in the body of the email, your attention to detail during the application stage, and many other ways. All those things contribute to the first impression that the recruiter forms about you.
But you have to have an excellent resume as well - one that gives them all the information they want including your career path for the last 10-20 years, your accountability in each position, and your most impressive achievements. If you don't give them the info they're looking for, you won't impress them. It doesn't get much simpler than that.
So what's different about your LinkedIn profile?
Say you post something on LinkedIn, comment on someone else's post, or "like" something you see - and it catches the attention of a recruiter. They then click on your name and go to your profile. Assuming you have no previous contact or relationship with that person, this is your first chance to impress them. They have never seen your resume and don't even know who you are. This is your big chance - something on your profile must impress them so they'll connect with you or send you a message.
So what information could you have on your LinkedIn profile that will impress them? It's obvious - the same information you have on your resume!
If it makes sense that a recruiter needs a clear picture of your career path, accountability, and accomplishments on your resume in order to decide whether you'd be a great candidate, then it also makes sense that they need to see the same thing on your profile in order to reach the same conclusion. After all, if there's something impressive enough about you to make them think, "Hmm, this person looks like a perfect fit for this great new opportunity I have" - why wouldn't you want that on both your resume AND your profile? What are you saving it for?
So my recommendation - if you're job searching - is to have basically the same information on your LinkedIn profile as you do on your resume. It doesn't have to be exactly the same word-for-word (although it can be - why not?), but the main information from your resume should also appear on your profile. If there's confidential information on your resume, leave it off your profile. Or if there's some other reason you don't want the same information publicly available on your profile, leave it off. But essentially it should be the same in terms of headline, summary, work history, and education.
Remember, some recruiters will view your profile after already reading your resume, but others will stumble upon your profile having never seen your resume. If you want to impress them, make sure the most compelling aspects of your background are in both places.
Best of luck!