Varnish

Varnish Cache is a web accelerator also famous as an HTTP accelerator. You can install it in front of any web server that speaks the HTTP protocol and configure it to cache the contents. Varnish Cache is really, really fast and will speed up your website. One of the important virtues of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to specify how incoming requests should be dealt with.

Memcached

Memcached is a general-purpose distributed memory object caching system for speeding up 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 object caching system uses a client'server architecture. The Memcached memory caching system is used by some of the most traffic-intensive websites on the web and is supported by famous web apps like Joomla and WordPress.

Node.js

Node.js is a platform for writing highly scalable Internet apps. Written in JavaScript, Node.js uses an event-based, asynchronous input/output model that makes it lightweight and efficient, suitable for high-performance data-intensive Internet applications. Node.js uses Google's V8 JavaScript engine, libUV, and several built-in libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source RDBMS. 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 version of InnoDB features substantial improvements in efficiency, security and usability. InnoDB provides the standard ACID database transaction features, along with declarative referential integrity support. InnoDB is included as standard in most binary distributions from MySQL AB.