LifeLog was a project of the Information Processing Technology Office of the Defense Advanced Research Projects Agency According to its bid solicitation pamphlet, it was to be "an ontology-based (sub)system that captures, stores, and makes accessible the flow of one person's experience in and interactions with the world in order to support a broad spectrum of associates/assistants and other system capabilities." The objective of the 'LifeLog' concept was "to be able to trace the 'threads' of an individual's life in terms of events, states, and relationships."
"LifeLog aims to compile a massive electronic database of every activity and relationship a person engages in. This is to include credit card purchases, web sites visited, the content of telephone calls and e-mails sent and received, scans of faxes and postal mail sent and received, instant messages sent and received, books and magazines read, television and radio selections, physical location recorded via wearable GPS sensors, biomedical data captured through wearable sensors, The high level goal of this data logging is to identify "preferences, plans, goals, and other markers of intentionality."[1]
The DARPA program was canceled in 2004 after criticism from civil libertarians concerning the privacy implications of the system.
Generically, the term "lifelog" or "flog" is used to describe a storage system that can automatically and persistently record and archive some informational dimension of an object's (object lifelog) or user's (user lifelog) life experience in a particular data category.