Web monitor

Most wikis maintain revision history for every web page in the system so you can easily visually compare changes between any two versions of the same page side-by-side, writes Amit Agarwal.

Most wikis maintain revision history for every web page in the system so you can easily visually compare changes between any two versions of the same page side-by-side. For instance, you can go to the history tab of any Wikipedia page and see how content of that page has changed over time.

Regular websites are a little different — they don't have history logs because the moment a site owner uploads new version of pages on to his web server, the previous ones are overwritten and gone forever.

Now if you like to have wiki-style history logs for your favourite web pages and also know what text has been added, removed or where the edits have happened since you last visited the site, check out Versionista.

What is Versionista?

Versionista is both a web page monitor and visual comparison tool. You supply a list of web addresses (or URLs) that you want to track with Versionista and it will send you an email alert when the site owner adds or edits something on those pages.

But what you'll like most about Versionista is the way it highlights changes in a web page — all the changes are colour coded and both versions of the page placed side-by-side so you can quickly compare the old content with the new.

This can be a great tool for tracking changes in legal documents, where every word matters. The free version of Versionista will track up to four different versions of the same page and you can monitor a maximum of five web pages.

Amit Agarwal writes a technology blog at www.labnol.org