Do you hate seeing advertisements while surfing the Internet? Well, if you have a browser such as Firefox or Chrome, you can easily install a plugin that will hide these adverts. The downside is, some malware will inject ads on pages that you surf in an attempt to make money from your page impressions so if you are hiding advertisements, you will not know that malware is infecting your device and locking itself into your registry in hopes of making it harder for you or a technician to remove and relaunch on each startup.
Wikipedia
The Wikipedia site is funded by those that donate proceeds. If you visit with your blocker off and see ads, you have confirmed that you are infected. It may take a while to discover but a faster way of seeing it to look up articles on tourism.