Understanding threats

A little background makes every other decision easier: how detection actually works, what a Kaspersky-style ban means, and the everyday habits that prevent more problems than any single piece of software.

• How antivirus actually works, explained in plain EnglishSignatures, heuristics, behavior monitoring and cloud checks: the four ways modern security software spots threats, what each one misses, and why nothing catches 100%.
• Kaspersky in the US: what the ban means and what to do if you used itKaspersky can no longer sell antivirus to US customers or send them updates. Here's what the ban says, why unsupported antivirus is a risk, and what happened with UltraAV.
• Six online safety habits that matter more than any antivirusUpdates, unique passwords, two-step verification, spotting phishing, safe downloads and backups: the free habits that prevent most real-world problems.
• Is this email attachment safe to open? How to check before you clickWhich file types are actually dangerous, why Outlook blocks some attachments automatically, and how to check a file safely before opening it.