| do-follow link | A do-follow link (or follow link) is a link which has not had the Nofollow rel attribute applied to it. This means generally speaking that it is a link which passes PageRank. Do-follow is not a value or attribute that is used in the code itself. |
| domain migration | The process of switching from one domain to another. |
| dynamic ip address | A random IP address that is assigned each time a computer connects to the network. |
| broken link | A link that leads to a 404 not found. Typically, a link becomes broken when: |
| profile density | Noun phrase. The ratio of measurable objects measured across a range of contexts. For example, Backlink profile density measures the ratio of inbound links to linking hosts. A spammy profile has a higher ratio than a natural profile (in which multiple links from the same host are more likely to be found). |