Varnish

Varnish Cache is a web accelerator also referred to as a caching HTTP reverse proxy. You can install it in front of any server that speaks HTTP and configure it to cache the content. Varnish Cache is really, really fast and will improve your site's loading speed. One of the major merits of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to choose how incoming requests should be dealt with.

Memcached

Memcached is a generic memory object caching system for boosting the load speed of dynamic database-powered web 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 memory object caching system is employed by some of the most traffic-heavy websites on the World Wide Web and is supported by famous web applications like Joomla and WordPress.

Node.js

Node.js is a software system for building scalable Internet applications. Written in JavaScript, Node.js uses an event-driven, non-blocking input/output model that makes it lightweight and effective, suitable for high-performance content-rich 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 database management system. A database engine is the primary software component that a database management system uses to create, read, modify and delete data from a database. The latest version of InnoDB features considerable improvements in efficacy, reliability and functionality. InnoDB provides the standard ACID-compliant database transaction properties, along with declarative referential integrity support. It is included by default in most binary distributions from MySQL AB.