Varnish

Varnish Cache is a web application accelerator also called 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 content. Varnish Cache is really, really fast and will boost the loading speed of your website. One of the major pluses of Varnish Cache is the flexibility of its configuration language, VCL, which allows you to determine how incoming requests should be handled.

Memcached

Memcached is a generic distributed memory object caching system for boosting the loading speed of dynamic database-powered 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 distributed memory object caching system uses a two-tier architecture. The Memcached distributed memory object caching system is employed by some of the most traffic-heavy web sites on the Internet and is supported by famous web apps like Joomla and WordPress.

Node.js

Node.js is a platform for writing scalable network apps. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, asynchronous I/O model that makes it lightweight and effective, great for high-performance content-rich apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of in-built libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source database management system. A storage engine is the underlying software component that a database management system uses to create, read, modify and delete data from a database. Its latest edition features significant improvements in efficiency, stability and functionality. InnoDB offers the standard ACID database transaction features, as well as foreign key support. InnoDB is included as standard in most binary distributions from MySQL AB.