Library of Congress to preserve Twitter posts

That Twitter message you just posted about your ham sandwich might now become part of history.

Twitter is donating its archives of tweets to the Library of Congress, going back to the first one posted by co-founder Jack Dorsey on March 21, 2006. It wasn't a profound moment, and Dorsey didn't come close to Twitter's 140-character limit for messages. He simply posted "Jack," according to the Library of Congress' archives.

Twitter and the Library of Congress announced their partnership Wednesday.

The Library of Congress wants to store tweets to give researchers a better way to revisit discussions of significant events, including the tweets that occurred after President Obama's election in 2008, during the protests in Iran last year and the earthquakes in Haiti and elsewhere this year.

Only tweets meant for public viewing will be available, though. Accounts with more restrictive privacy settings won't be included.

There's also another limitation: Twitter said the Library of Congress won't be able to offer access to specific tweets until six months after they're posted. That means the Library of Congress' archive will always been missing billions of tweets, based on the 55 million daily tweets that Twitter says it's now processing.

In a separate deal announced Wednesday, Internet search leader Google also began to draw upon tweeting history with a new tool that will allow people to sift through Twitter messages about specific topics by day, month or year. Only tweets going back to Feb. 11 of this year will be available initially, but Google eventually expects to gain access to all the messages dating back to Twitter's birth.