Varnish

Varnish Cache is a web accelerator also famous as a caching HTTP reverse proxy. You can install it in front of any web server that speaks the HTTP protocol 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 important strengths of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which enables you to determine how incoming requests should be tackled.

Memcached

Memcached is a general-purpose memory object caching system for speeding up dynamic database-powered websites. It is used to lower 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 distributed memory object caching system is employed by some of the most traffic-intensive websites on the Internet and is supported by popular CMSs 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-based, asynchronous I/O model that makes it lightweight and efficient, great for high-performance content-heavy Internet 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 relational database management system. A storage engine is the principal software component that a DBMS uses to create, read, modify and delete data from a database. The latest edition of InnoDB features significant improvements in efficiency, reliability and usability. InnoDB provides the standard ACID-compliant transaction properties, as well as foreign key support. InnoDB is included as standard in most binaries distributed by MySQL AB.