What Are “Runlevels” on Linux?

When a Linux system boots, it enters its default runlevel and runs the startup scripts associated with that runlevel. You can also switch between runlevels – for example, there’s a runlevel designed for recovery and maintenance operations.

What Is a Browser Cookie?

We’ve recently been hearing about tracking cookies and laws in the European Union forcing websites to explain their use of cookies to their visitors. If you’re wondering what cookies are and what all the fuss is about, you’re not alone.

What Is IPv6, and Why Does It Matter?

IPv4 addresses on the public Internet are running low. Microsoft paid $7.5 million for Nortel’s 666,624 IP addresses when Nortel went bankrupt in 2011 – that’s over $8 an IP address. IPv4 has technical problems, and IPv6 is the solution.

Is UPnP a Security Risk?

UPnP comes enabled by default on many new routers. At one point, the FBI and other security experts recommended disabling UPnP for security reasons. But how secure is UPnP today? Are we trading security for convenience when using UPnP?

Is Windows ReadyBoost Worth Using?

Connect a USB stick to a Windows computer – even on Windows 8 – and Windows will ask if you want to speed up your system using ReadyBoost. But what exactly is ReadyBoost, and will it actually speed up your computer?

How Antivirus Software Works

Antivirus programs are powerful pieces of software that are essential on Windows computers. If you’ve ever wondered how antivirus programs detect viruses, what they’re doing on your computer, and whether you need to perform regular system scans yourself, read on.