According to a recent ads report released by Google, the company says it removed 3.2 billion ads from its platforms in 2017, almost double the amount they removed in 2016. That equates to the removal of around 100 ads per second. These high numbers are a result of Google cracking down on malicious ads.

Scott Spencer, director of product management for Google’s Sustainable Ads unit, explained in a blog post that “bad ads can ruin the online experience for everyone. They promote illegal products and unrealistic offers. They can trick people into sharing personal information and infect devices with harmful software. Ultimately, bad ads pose a threat to users, Google’s partners, and the sustainability of the open web itself.”

Google’s increasing ad suppression has led many small business owners who rely on AdWords campaigns to wonder how they’ll be affected. Here’s what they should know.

Google’s primary efforts are to get rid of phishing scams that fool people into revealing personal information, links to sites that try to trick people into installing malware, and ads placed on sites that copy legitimate news stories. Ads that aren’t maliciously intentioned and represent the advertising of a legitimate business will not be blocked.

There are, however, a few exceptions. Google’s ad policy spells out some of the ad content it won’t accept. This content includes alcohol, tobacco, and gambling related ads. It also encompasses certain healthcare-related content that advocates for the online sale of prescription drugs or unapproved pharmaceuticals and supplements.

Of the ads Google blocked in 2017, 79 million were attempting to send users malware-laden websites, 66 million were “trick-to-click” ads, and 48 million were attempting to install unwanted software on users’ computers. These ads make up the bulk of what Google blocks.

As long as small business owners stay aware of the types of ads Google blocks, they shouldn’t have any problem advertising their services. Google plans to keep cracking down on malicious ads, meaning there’s a chance their policies and practices may change. It’ll be interesting to see if they break their record again next year.