Content:Mobile application servers, Application servers, and web servers serve similar purposes: they are pieces of middleware that connect back-end systems to the users that need to access them, but the technology in each of the three differs. Application servers—developed before the ubiquity of web-based applications—expose back-end business logic through various protocols, sometimes including HTTP, and manage security, transaction processing, resource pooling, and messaging. When web-based applications grew in popularity, application servers did not meet the needs of developers, and the web server was created to fill the gap.Web servers provide the caching and scaling functionality demanded by web access and not provided by application servers. They convert requests to static content, and serve only HTTP content. Over time, application servers and web servers have morphed from two previously distinct categories, blended features, and arguably have merged.Mobile application servers are on a similar path. The emergence of mobile devices presents the need for functionality not anticipated by the developers of traditional application server developers, and mobile application servers fill this gap. They take care of the security, data management and off-line requirements not met by existing infrastructure, and present content exclusively in REST.Over time, these three categories may fully merge and be available in a single product, but the root functions differ.