Varnish

Varnish Cache is a web accelerator also famous as an HTTP accelerator. You can install it in front of any server that speaks the HTTP protocol and configure it to cache the content. Varnish Cache is very, very fast and will boost your website's loading speed. One of the main advantages of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to define how incoming requests should be tackled.

Memcached

Memcached is a generic distributed memory caching system for boosting the loading speed of dynamic database-driven 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 caching system uses a client'server architecture. The Memcached distributed memory object caching system is used by some of the most frequently visited websites on the Internet and is supported by popular web apps 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 effective, suitable 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 database engine is the principal software component that a database management system uses to create, read, update and delete data from a database. The latest release of InnoDB offers significant improvements in efficiency, security and usability. InnoDB provides the standard ACID-compliant transaction properties, along with referential integrity support. It is included by default in most binaries distributed by MySQL AB.