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 contents. Varnish Cache is very, very fast and will increase your website's loading speed. One of the major merits of Varnish Cache is the flexibility of its configuration language, VCL, which allows you to specify how incoming requests should be handled.

Memcached

Memcached is a generic distributed memory object caching system for boosting the load speed of dynamic database-driven web sites. 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 frequently visited websites on the Internet and is supported by famous web apps like Joomla and WordPress.

Node.js

Node.js is a software system for building highly scalable network apps. Built on Chrome's JavaScript runtime, Node.js uses an event-based, asynchronous input/output model that makes it lightweight and effective, suitable for high-performance content-rich network apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of in-built libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source database management system. A storage engine is the primary software component that a DBMS uses to create, read, modify and delete data from a database. Its latest version features substantial improvements in efficacy, reliability and functionality. InnoDB provides the standard ACID-compliant database transaction properties, as well as foreign key support. InnoDB is included as standard in most binary distributions from MySQL AB.