Varnish

Varnish Cache is a web accelerator also popular as a caching HTTP reverse proxy. You can install it in front of any server that speaks HTTP and configure it to cache the content. Varnish Cache is very, very fast and will make your site load much faster. One of the key strengths of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to determine how incoming requests should be handled.

Memcached

Memcached is a generic distributed memory caching system for increasing the load speed of dynamic database-driven sites. It is used to reduce 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 caching system is used by some of the most popular web sites on the Internet and is supported by famous web apps like Joomla and WordPress.

Node.js

Node.js is a software platform for writing scalable network applications. Built on Chrome's JavaScript runtime, Node.js uses an event-based, asynchronous input/output model that makes it lightweight and efficient, perfect for real-time content-intensive 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 database management system. A database engine is the underlying software component that a DBMS uses to create, retrieve, modify and delete data from a database. Its latest edition features substantial improvements in performance, reliability and functionality. InnoDB provides the standard ACID database transaction features, as well as foreign key support. InnoDB is included by default in most binary distributions from MySQL AB.