Below is a Screen Shot of a Pop Up Ad that plays on your fear of spyware to get you to click. If you click on this pop up the company says they do not download any adware onto your computer. If you click NO, it still installs a tracking cookie and takes you to the companies website. By definition, this pop up is adware. Notice what it says in the lower left corner of the pop up.
Hint: advertisement.
I wonder why it's in lower case and faded? This is a criminal dressed up like a cop.

Always use the X ,in the upper right corner of the pop up, to back out of a pop up.
Interesting fact: One company was sued and lost for using the X as a link to their website.

A Tracking Cookie was installed on my computer shown below circled in red. Notice the same company is listed above in the address bar, also circled in red. An AntiSpyware program found it after I closed the pop up out.