Varnish

Varnish Cache is a web application accelerator also called as an HTTP accelerator. You can install it in front of any web server that speaks HTTP and configure it to cache the content. Varnish Cache is really, really fast and will improve the loading speed of your site. One of the chief features of Varnish Cache is the flexibility of its configuration language, VCL, which enables you to determine how incoming requests should be tackled.

Memcached

Memcached is a general-purpose memory caching system for boosting the load speed of dynamic database-driven 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 memory object caching system uses a client'server architecture. The Memcached memory object caching system is used by some of the most traffic-heavy sites on the World Wide Web and is supported by popular Content Management Systems like Joomla and WordPress.

Node.js

Node.js is a platform for building highly scalable Internet applications. Built on Chrome's JavaScript runtime, Node.js uses an event-based, non-blocking input/output model that makes it lightweight and efficient, great for high-performance data-rich network 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 database management system. A database engine is the principal software component that a database management system uses to create, retrieve, update and delete data from a database. Its latest release features serious improvements in performance, stability and usability. InnoDB provides the standard ACID-compliant transaction properties, along with foreign key support. InnoDB is included as standard in most binaries distributed by MySQL AB.