Varnish

Varnish Cache is a web application accelerator also referred to as a caching HTTP reverse proxy. You can install it in front of any server that speaks the HTTP protocol and configure it to cache the contents. Varnish Cache is really, really fast and will make your web site load much faster. One of the important features of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to specify how incoming requests should be handled.

Memcached

Memcached is a generic distributed memory object caching system for increasing the loading speed of dynamic database-powered web sites. It is used to decrease 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 distributed memory caching system uses a two-tier architecture. The Memcached memory caching system is employed by some of the most frequently visited websites on the World Wide Web and is supported by famous web applications like Joomla and WordPress.

Node.js

Node.js is a platform for building scalable network applications. Written in JavaScript, Node.js uses an event-driven, asynchronous I/O model that makes it lightweight and efficient, great for high-performance content-intensive Internet apps. Node.js uses Google's V8 JavaScript engine, libUV, and several in-built libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source RDBMS. A storage engine is the principal software component that a database management system uses to create, read, update and delete data from a database. The latest release of InnoDB features considerable improvements in efficacy, reliability and functionality. InnoDB provides the standard ACID-compliant database transaction properties, along with foreign key support. InnoDB is included as standard in most binary distributions from MySQL AB.