Social media plugins allow websites to integrate social media features like the "Like" button directly into their pages. Popular plugins include the Facebook "Like" button and other social sharing buttons that make it easy for visitors to engage with content on social networks. These plugins are typically implemented through short snippets of JavaScript code or iFrames that pull social features from the external platforms. When visitors click on social plugins, it can help drive traffic and engagement back to the original website and share content more widely across social networks.