Varnish

Varnish Cache is a web accelerator also called as an HTTP accelerator. 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 boost the loading speed of your site. One of the chief attributes 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 general-purpose memory caching system for boosting the loading speed of dynamic database-driven websites. 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 client/server architecture. The Memcached memory caching system is used by some of the most traffic-hungry web sites on the World Wide Web and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a software platform for building highly scalable Internet apps. Written in JavaScript, Node.js uses an event-based, non-blocking I/O model that makes it lightweight and efficient, excellent for real-time content-heavy applications. 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 relational database management system. A storage engine is the main software component that a DBMS uses to create, retrieve, modify and delete data from a database. Its latest version features substantial improvements in efficiency, dependability and functionality. InnoDB offers the standard ACID-compliant transaction properties, as well as declarative referential integrity support. It is included as standard in most binaries distributed by MySQL AB.