Varnish

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

Memcached

Memcached is a generic distributed memory caching system for increasing the speed of dynamic database-powered web sites. It is used to decrease the number of times an external data source (such as a database or API) is read by caching data and objects in RAM. The Memcached system uses a client'server architecture. The Memcached distributed memory caching system is used by some of the most popular web sites on the web and is supported by popular web applications like Joomla and WordPress.

Node.js

Node.js is a platform for building scalable Internet applications. Written in JavaScript, Node.js uses an event-based, asynchronous input/output model that makes it lightweight and efficient, perfect for real-time data-heavy Internet apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of built-in libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source relational database management system. A database engine is the underlying software component that a DBMS uses to create, read, update and delete data from a database. Its latest edition features serious improvements in efficiency, security and usability. InnoDB offers the standard ACID-compliant database transaction properties, along with declarative referential integrity support. It is included as standard in most binary distributions from MySQL AB.