It's a highly customizable high-performance page cache for dynamic content built into LiteSpeed Web Server. Similar to Varnish but more efficient!
LSCache's features are very similar to those in Apache mod_cache, but implemented in a more efficient way. LiteSpeed cache works like Varnish. It is an output cache for dynamic contents, so the usage is not limited to PHP pages. Unlike Varnish, LiteSpeed cache is built into LiteSpeed's web server, thus eliminating one layer of reverse proxy. This translates into higher efficiency for static contents.
LiteMage Cache is the world's fastest full page caching solution for Magento. Built on top of LSCache and designed specifically for Magento, LiteMage can assemble both public and private blocks from cache by hole-punching through ESI to deliver the fastest full-page caching around.