Parallax Scrolling

The percentage of recipients who unsubscribe from an email after it is sent. In large-scale marketing, some unsubscribes are expected, but it’s a metric that can be monitored to ensure you aren’t putting off your audience with either the frequency or messaging of your email advertising.

A structured file that catalogs and organizes a website, for easy, readable access by search engines.

A sitemap should be submitted to major search engines when you create a site, and also any time you have large-scale restructuring of the site. New sitemaps do not need to be generated every time a new page goes live. These will usually be crawled by search engines and added to the number of indexed pages on a site.

Linked text on your website that links to another domain. External links can provide informational value for those reading your site, and also signal to search engines which external sites have content that is related to yours.