Java is a programming language that developers use to create applications on your computer. Chances are you've downloaded a program that required the Java runtime, and so you probably have it installed it on your system. Java also has a web plug-in that allows you to run these apps in your browser.
Is Java Insecure?
Java has two parts: the runtime that runs on your computer (and lets you run Java apps), and the browser plug-in that comes along with it. When people talk about Java being insecure, they're talking about the browser plug-in. Java apps themselves aren't inherently insecure, it's the browser plug-in that causes problems.
In fact, Kaspersky Lab says that the Java browser plug-in was responsible for 50 percent of all cyber attacks last year, and security experts are constantly advising that you disable it in your browser. It opens up a number of holes that can allow criminals to steal passwords, credit card numbers, and other personal information. And, as you've noticed from reading news on the web, new security holes are popping up all the time.
Should I Disable it?
Chances are, you don't even need the Java browser plug-in. To disable Java in your browser, head to your browser's plug-in page. In Chrome, you can do this by typing chrome://plugins into the address bar, and in Firefox, you can do so by going to Tools > Add-Ons > Plugins. Then, just find Java and click Disable. That's all it takes!
The browser plug-in is the security problem in question, but the Java runtime has its own annoyances—like constantly nagging you for updates, taking up space in your system tray, and (when you first install it) because it likes to install things like toolbars on your system. For these reasons, we generally recommend uninstalling the Java runtime too, just for the convenience. If you find that an app asks for Java after the fact, you can always reinstall, as long as you keep that browser plugin disabled. To uninstall Java, open up the Start menu, search for uninstall a program, press Enter, and choose Java from the uninstall list. You'll probably be happy you did.