A Lineage is a family of individuals sharing the same heritage, usually by blood. On this site, a Lineage possesses one unique Trait separate from a Descendent's normal Traits. This Lineage Trait is shared among all Descendants of a Lineage, no matter their blood relation. Even adopted Descendants possess a Lineage's Trait due to fate playing a role in a character's development! Keep in mind - Descendants of a Lineage don't need to be of the same Race. Currently there is no limit to the number of Lineages a single player is allowed to RP, but with each Lineage there must be a separate account made.
A Descendant is the actual, player controlled character with which you RP. Up to 4 Descendants are allowed to be active within one Lineage at any given time (one per Timeline). If all 4 character slots within a Lineage are taken up, an active Descendant must be made inactive by any means you see fit; death is the most obvious form of inactivity, but retirement is another alternative. Retirement of a Descendant is permanent, but unlike death - a retired Descendant is able to be RPed like an NPC and make cameo appearances! Anyway, death or retirement - think carefully about such a permanent decision. Only Heirlooms are transferred upon death/retirement (unless the Heirloom is stolen); money and everything else is NOT transferred!