Varnish

Varnish Cache is a web accelerator also famous as an HTTP accelerator. You can install it in front of any web server that speaks HTTP and configure it to cache the content. Varnish Cache is very, very fast and will boost the loading speed of your site. One of the main merits of Varnish Cache is the flexibility of its domain-specific 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 speed of dynamic database-powered websites. It is used to decrease 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 caching system uses a client/server architecture. The Memcached memory object caching system is used by some of the most traffic-heavy sites on the Internet and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a software system for writing highly scalable network apps. Written in JavaScript, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and effective, perfect for high-performance data-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 RDBMS. A database engine is the primary software component that a DBMS uses to create, read, modify and delete data from a database. Its latest release offers significant improvements in performance, reliability and usability. InnoDB provides the standard ACID-compliant transaction attributes, as well as referential integrity support. InnoDB is included as standard in most binaries distributed by MySQL AB.