Delta Search (delta-search.com) is a browser hijacker promoted using browser toolbars (i.e. Delta toolbar and Babylon toolbar). While this website may seem legitimate, computer users commonly visit this site unwillingly via enforced redirection. These redirect issues are caused by Delta toolbar - once the user installs the toolbar on Internet Explorer, Google Chrome, and Mozilla Firefox, their browser is changed in a way that the homepage and default search engine will always be assigned to delta-search.com.
This browser hijacker gets onto a computer through means of downloading/installing Babylon Toolbar or download websites (such as softonic.com, download.com, etc.) that bundle the toolbar via "download clients". This is categorized as adware, and users are strongly advised to eliminate this browser add-on from their computers.