Copyscape is an online plagiarism detection tool that enables you to automatically scan the web and find out whether you have duplicated someone's work in your content. By now, you know that duplicate content is a No-Go zone when dealing with Google and you can be punished severely for plagiarism.
How it works
Copyscape features two options: free and paid versions. To figure out which version is ideal for your work, you head over to their site and check out the two versions. Copyscape's free plagiarism checker allows you to search for copies of your content on the web. All you need to do is to copy the URL of the page or blog you intend to check and click on the "Go" button. Copyscape will scan the web for duplicate content and if it finds any, it will return results of copied content.
If you want to use the paid/premium version, you need to head over to the sign-up page and register for an account. Next, log in and purchase credits. Currently, the lowest limits for credits you can buy are worth $10. Premium credits are priced at $0.05.
For people using PayPal as their preferred payment method, they have to buy a minimum of 200 credits valid for 1 year. Once you purchase the credits, you are ready to start the plagiarism checking process.
From the main page, there is a box labeled "Paste text or URL" You paste the content or URL you intend to check in the box and click on the "Premium search" button.
In a few moments, Copyscape will return results showing you whether your text or URL contains duplicate content or not. You will also be provided with a plagiarism report page from which you can see links of the original content. Since you can see the copied text from the source files on the report, you can tell how much of the duplicate content is in your text.
Conclusion
Copyscape is an efficient, handy and highly effective plagiarism checker that cuts to the chase and give you the desired results without any fanfare. However, to get the best from this plagiarism checker, you have to use the paid or premium version of Copyscape. In spite of its efficiency, its services are not highly priced, so, I would definitely recommend it for anyone doing serious web content writing.