Varnish

Varnish Cache is a web application accelerator also referred to 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 very, very fast and will increase the loading speed of your website. One of the main pluses of Varnish Cache is the flexibility of its configuration language, VCL, which permits you to define how incoming requests should be handled.

Memcached

Memcached is a generic memory caching system for speeding up dynamic database-driven sites. It is used to reduce the number of times an external data source (such as a DB or API) is read by caching data and objects in RAM. The Memcached memory caching system uses a client'server architecture. The Memcached memory object caching system is used by some of the most frequently visited web sites on the World Wide Web and is supported by popular web applications like Joomla and WordPress.

Node.js

Node.js is a software system for writing scalable Internet applications. Built on Chrome's JavaScript runtime, Node.js uses an event-based, asynchronous input/output model that makes it lightweight and efficient, perfect for real-time content-rich network apps. Node.js uses Google's V8 JavaScript engine, libUV, and several built-in libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source relational database management system. A database engine is the main software component that a database management system uses to create, read, modify and delete data from a database. The latest edition of InnoDB features serious improvements in efficacy, dependability and functionality. InnoDB provides the standard ACID transaction attributes, as well as foreign key support. InnoDB is included as standard in most binaries distributed by MySQL AB.