Smarty是一个使用PHP写出来的模板引擎，是目前业界最著名的PHP模板引擎之一。它分离了逻辑代码和外在的内容，提供了一种易于管理和使用的方法，用来将原本与HTML代码混杂在一起PHP代码逻辑分离。简单的讲，目的就是要使PHP程序员同前端人员分离，使程序员改变程序的逻辑内容不会影响到前端人员的页面设计，前端人员重新修改页面不会影响到程序的程序逻辑，这在多人合作的项目中显的尤为重要。

Notable smarty 3.1 changes/features:

Smarty 2 BC removed from codebase, use SmartyBC.class.php for this

Full UTF-8 compatibility with all plugins

Default Template Handler for handling non-exiting template files

Default Config Handler for handling non-exiting config files

Default Plugin Handler for handling non-exiting plugin files

{block hide} feature when no corresponding child block is found

{setfilter}{/setfilter} to apply filters to a specific block of template code

Improved Template Resource API

Improved Cache Resource API

Relative paths in template files {include file="../header.tpl"}

Access to specific $template_dir via array index

Access multiple template resources with extends: feature

Simple global HTML escapement option with escape_html property

Compile-Check on cache miss option

Automatic template recompile on Smarty upgrade

New Getters/Setters for main Smarty directory configuration