These crawls are part of an effort to archive pages as they are created and archive the pages that they refer to. That way, as the pages that are referenced are changed or taken from the web, a link to the version that was live when the page was written will be preserved.
Then the Internet Archive hopes that references to these archived pages will be put in place of a link that would be otherwise be broken, or a companion link to allow people to see what was originally intended by a page's authors.
Having trouble using Twitter buttons or embedding Tweets on your website? Below are some answers to common problems with these features:
Check the Issue Tracker for similar issues or requests. If you find what you're looking for, subscribe to the issue to indicate your interest.
Search the Discussions for similar issues and requests. If you find an active topic about the issue, use that thread to continue discussing it.
If you can't find your issue in either the tracker or in discussions, consider starting a discussion topic. By creating a discussion topic, you can discuss the problem with Twitter employees and third party developers to rule out any already-known issues, common developer errors, or surface other information regarding Twitter the service to help resolve your potential issue.
Note: Twitter buttons cannot be added to email signatures.
