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 speed up your web site. One of the chief advantages of Varnish Cache is the flexibility of its configuration language, VCL, which permits you to specify how incoming requests should be handled.

Memcached

Memcached is a generic memory object caching system for boosting the loading speed of dynamic database-driven sites. It is used to lower 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 traffic-intensive websites on the World Wide Web and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a software system for building scalable network apps. Written in JavaScript, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and efficient, great for high-performance content-rich Internet applications. 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 relational database management system. A storage engine is the principal software component that a DBMS uses to create, read, modify and delete data from a database. Its latest version features significant improvements in performance, security and functionality. InnoDB provides the standard ACID-compliant database transaction features, as well as foreign key support. It is included as standard in most binary distributions from MySQL AB.