In the world of SEO, “duplicate content” refers to content that is repeated on numerous pages of the same website word for word. It’s bad to have duplicate content on your site for two reasons. First, it provides a bad user experience. If a visitor is clicking through the pages of your site and realizes that they are all the same they will essentially be wasting their time and will become frustrated and leave the website. Second, the search engines frown upon it. They view duplicate content as a spammy way to manipulate the search engines and get your site to appear more than once in a search engine result, increasing the likelihood that a user will click over to your site. If a search engine catches you using this tactic they will likely penalize you for it.
It’s important to note that duplicating content isn’t always done maliciously. For example a web page, and the “printer friendly” version of that page are technically duplicate content but the search engines realize this and don’t penalize for it. In some cases people just don’t have the knowledge and don’t realize that they are creating duplicate content. Some web developers don’t build sites with SEO in mind and may create two homepages: the regular one and one that is listed as the “default” or “index”. While the content is the same, the pages are different and each have different inbound links. Splitting the link value like this is very bad. One of the key components of SEO is building quality, inbound links to your site which builds trust with the search engines. The more that you have, the better. If half of these links are going to the homepage and half are going to the “index” homepage neither one of them is reaping the full benefit of these links.
Therefore, it’s important to watch out for duplicate content on your web pages. The search engines like new, unique content on every page. It’s likely that the content on each may be similar since they are all a part of one website which is generally about one thing. However, if you notice that the content is too similar make some tweaks to it, or just put it all on one page. Your visitors and the search engines will appreciate it.