Tweeting is an ephemeral singular act with a multiplication effect and a permanent memory.

FORBES: Elizabeth Taylor's Last Tweets: @DameElizabeth on Love, Death and Kim Kardashian

Many reached for their cameras, trying to capture a permanent memory of the moment.

CNN: Witnesses share emotion of inauguration festivities

He is the executive director of the drafting committee on UCITA. "The permanent staff person, the corporate memory, " is how he describes his job.

CNN: Opponents blast proposed U.S. software law

That way, if the power went away, the battery would have enough charge to write the data from the memory to some other more permanent location.

FORBES: Nanotech Meets Computer Memory

The details of that event are carved in my memory by an emotional chisel that has left permanent, deep-rutted scars.

FORBES: Where Were You On 9/11?

"Within the living memory of all of us, Republicans were on track to become a permanent majority, " he said in a statement.

CNN: Scramble is on to replace Congressional leaders