Domain investing (or "domaining") is the practice of registering, holding, and reselling domain names as an asset, rather than registering a domain purely to build a website on it. An investor might hold ten domains as a side interest or several hundred thousand as a full-time business; the underlying activity is the same: identify domains likely to gain value, register or acquire them, and eventually sell, lease, or develop them.

This is a fully legitimate, longstanding practice within the domain industry, distinct from cybersquatting (registering a domain in bad faith to profit from someone else's trademark, which is a real dispute category; see What Is a UDRP Domain Dispute? on UDRP). Most domain investors deal in generic, descriptive, or otherwise inherently valuable names, not trademarked ones.

If you're managing more than a handful of domains, most of the concepts in this section — categories, bulk tools, at-cost pricing — exist specifically to make that workable at scale.