Public service announcement: Be careful where you download Java from.

Actually, the first question should be whether you need Java to be installed to begin with.

Very few applications depend on it. The main reason to have it installed these days is Minecraft, the Windows installer for which now comes with its own Java Runtime Environment (JRE). 

If you really need the Java plug-in, don't download it from java.com. The installer you get from there is notorious for bundling the Ask toolbar for Windows; Oracle have now moved on to bundling the toolbar with the Java installer for Mac OS X as well. 

Scumbags.

If you want to download Java without any bundled crapware, go to java.oracle.com. The website may seem jarring to the non-technical user at first, but it's fairly easy to find the right Java Runtime Environment for your needs:

1. Click on Java SE 8 Update 40 (the current version at the time I'm writing this).

2. Click on the 'Download' button labelled JRE.

3. Check the 'Accept License Agreement' radio button, then download the Java Runtime Environment for your computer. Mac OS X users will want to go with the first option (jre-8u40-macosx-x64.dmg) for their platform; for Windows users the Windows x86 Offline installer is recommended. I

There you have it - you've downloaded a clean Java installer without any bundled toolbar crapware.