On Feb. 6, technology companies, educators and others mark Safer Internet Day and urge people to improve their online safety. Many scholars and academic researchers around the U.S. are studying aspects of cybersecurity and have identified ways people can help themselves stay safe online. Here are a few highlights from their work.

1. Passwords are a weakness

With all the advice to make passwords long, complex and unique – and not reused from site to site – remembering passwords becomes a problem, but there’s help, writes Elon University computer scientist Megan Squire:

“The average internet user has 19 different passwords. … Software can help! The job of password management software is to take care of generating and remembering unique, hard-to-crack passwords for each website and application.”

That’s a good start.

2. Use a physical key

To add another layer of protection, keep your most important accounts locked with an actual physical key, writes Penn State-Altoona information sciences and technology professor Jungwoo Ryoo:

“A new, even more secure method is gaining popularity, and it’s a lot like an old-fashioned metal key. It’s a computer chip in a small portable physical form that makes it easy to carry around. The chip itself contains a method of authenticating itself.”

Just don’t leave your keys on the table at home.

3. Protect your data in the cloud

Many people store documents, photos and even sensitive private information in cloud services like Google Drive, Dropbox and iCloud. That’s not always the safest practice because of where the data’s encryption keys are stored, explains computer scientist Haibin Zhang at University of Maryland, Baltimore County:

“Just like regular keys, if someone else has them, they might be stolen or misused without the data owner knowing. And some services might have flaws in their security practices that leave users’ data vulnerable.”

So check with your provider, and consider where to best store your most important data.

4. Don’t forget about the rest of the world

Sadly, in the digital age, nowhere is truly safe. Jeremy Straub from North Dakota State University explains how physical objects can be used to hijack your smartphone:

“Attackers may find it very attractive to embed malicious software in the physical world, just waiting for unsuspecting people to scan it with a smartphone or a more specialized device. Hidden in plain sight, the malicious software becomes a sort of ‘sleeper agent’ that can avoid detection until it reaches its target.”

It’s a reminder that using the internet more safely isn’t just a one-day effort.