WordPress 2.1 introduced an autosave feature that automatically saves the current post being edited every 60 seconds. This is a useful feature because it helps prevent the loss of content if your PC crashes, or locks up, or if you accidentally decide to visit another site before saving your work.
Many WordPress users are not aware that this feature exists, but for others, the 60 second default frequency can be annoying. Earlier version of the autosave feature caused problems with some WordPress installations, but the feature tends to work much better with current versions of WordPress. The autosave feature is now pretty subtle. To clarify what the feature does, WordPress automatically saves the draft of a current post being edited if it detects a change since the last time it saved the post.
You can change the timing of the autosave feature by adding the following line of code to the wp-config.php file.
The numeric value is the time in seconds, so using a value of 300 means that the post being edited will be automatically saved every 300 seconds, which is every 5 minutes.
If you do not like the WordPress autosave feature, you can set the value to something very high, but I personally advise against doing so. A 5 or 10 minute interval is probably reasonable. Your work is vulnerable to a power failure or an accidental closure of the browser window if the work is not saved periodically. I remember losing a lot of work a few years ago in a previous version of WordPress because I was not saving my work and I accidentally closed the browser window. It took over an hour to recreate what I lost. The best lessons are frequently learned the hard way.