As with most things online, the site keeps a virtual record of all of your activity. You may not even be aware of it, but every selection you've made is documented. There is a way, however, to purge that record permanently. To delete your Netflix viewing history, however, you must cancel your account and then resubscribe.
Unfortunately, Netflix has disabled these features, and there are no official options to remove or hide the recently watched content on your Netflix account apart from removing your account and creating it again. See this update instead:
1. Sign in to Netflix using your username and password.
2. Click on "Your Account & Help" in the upper right-hand corner of the screen. Find the section called "Account Information." Click on "Cancel Membership."
3. Read each item carefully and understand that by doing this you will not only be purging your viewing and rental history, but your queue as well. Click the box on the bottom of the page next to the sentence that reads, "I accept and understand the terms of cancellation and want to cancel my account." Then click "Complete Cancellation."
After you have canceled your account, you can resubscribe to Netflix using the same billing information. You can also rebuild your movie queue.