Linkbaiting is the practice of crafting content that is designed to get other content producers to link to it. The purpose is increasing the number of inbound links to your content and thus improving its performance in search engine results.
The most important element of linkbaiting is creating compelling content, something that the reader finds value in. Examples of link bait, in this context, include breaking news, striking images, info graphics, controversy, humor, educational material and applications. If your content has value for readers, they are likely to share the link.