Varnish

Varnish Cache is a web accelerator also known as an HTTP accelerator. You can install it in front of any server that speaks HTTP and configure it to cache the content. Varnish Cache is really, really fast and will improve the loading speed of your website. One of the key merits of Varnish Cache is the flexibility of its domain-specific language, VCL, which enables you to determine how incoming requests should be tackled.

Memcached

Memcached is a generic memory caching system for increasing the load speed of dynamic database-powered websites. It is used to lower the number of times an external data source (such as a database or API) is read by caching data and objects in RAM. The Memcached system uses a client'server architecture. The Memcached system is employed by some of the most regularly visited sites on the web and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a platform for writing scalable network applications. Written in JavaScript, Node.js uses an event-driven, asynchronous I/O model that makes it lightweight and efficient, perfect for real-time content-heavy applications. Node.js uses Google's V8 JavaScript engine, libUV, and several in-built libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source RDBMS. A database engine is the underlying software component that a DBMS uses to create, read, update and delete data from a database. The latest release of InnoDB features considerable improvements in efficacy, reliability and usability. InnoDB offers the standard ACID-compliant database transaction attributes, along with foreign key support. It is included by default in most binary distributions from MySQL AB.