Advertisers were also more frequently using performance-based ads - where they pay only when someone clicks on the AD or buys something after seeing the AD.

广告主也更频繁地使用基于表现的广告，这样他们只有在用户看广告之后点了广告或购买物品时才要付费。

youdao

Many viruses are triggered when an unsuspecting user clicks on an attachment (often Visual Basic), thinking it's something nice from a friend or colleague.

CNN: Technology - Analysis: Understanding viruses