This post caters to more of the technical audience so if there is anything you don’t understand, please feel free to reach out to me with any specific questions you may have.
Meta tags are a way to send signals to the search engines to tell them specific information about a web page. Defined by Wikipedia they are “data about data.” There are two different types of meta data, structural and descriptive. Meta data is useful because it helps search engines in terms of displaying and indexing data when search results are returned.
Meta Index, Noindex, Follow and Nofollow Tags
One of the more popular and important meta tags are the robots tag. This single line of code can make or break your sites performance in the SERPs. I’ve seen this tag implemented incorrectly more often than I care to mention so this is usually one of the first places I check when performing a technical audit.
According the official robots guidelines, there are three correct ways to set up this tag.
<meta name=”robots” content=”noindex, follow”>
<meta name=”robots” content=”index, nofollow”>
<meta name=”robots” content=”noindex, nofollow”>
Here is a breakdown of how those tags work:
How the Meta Robots Tags Work
The most common talked about robots tag is noindex,nofollow. What this tag does is tell search engines not to index that particular web page as well as not to follow any of the links on that page. Keep in mind that the NOINDEX tag does not mean a particular page will be ignored by search engine spiders, they will just not be displayed in the SERPs.
The NOINDEX, FOLLOW tag may be used for something like a login page has great navigation but little value to the websites performance. The goal here is to keep a particular page out of the SERPs but still crawl any links found here to their destination.
Since there is usually limited content on login pages, you may want to consider employing a tag like this to prevent it from being indexed, but still pass along any link value to other pages within the site.
Lastly, the INDEX, NOFOLLOW tag is one that I don’t see too often. This will allow search engines to index your pages content but will not crawl any of the links on that page. A tag like this would generally be used for a new page on a new site that you would like to be indexed, but the other pages are not completed or live yet.
Are There More Meta Tags?
The list of meta tags goes on to include noimageindex which will not index images, noodp which block search engines from using the description from DMOZ, noarchive prevents search engines from showing cached versions of a page. For a complete list of additional meta tags, check out this post by Joost de Valk
If you’d like to see more examples of meta data or any additional technical topics covered, please reach out to me and I will do my best to comply.