Varnish

Varnish Cache is a web accelerator also famous as an HTTP accelerator. You can install it in front of any server that speaks HTTP and configure it to cache the content. Varnish Cache is really, really fast and will increase your website's speed. One of the key pluses of Varnish Cache is the flexibility of its configuration language, VCL, which permits you to choose how incoming requests should be tackled.

Memcached

Memcached is a general-purpose distributed memory caching system for boosting the loading speed of dynamic database-powered 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 distributed memory caching system uses a client/server architecture. The Memcached system is employed 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 software platform for building highly scalable network applications. Written in JavaScript, Node.js uses an event-driven, non-blocking input/output model that makes it lightweight and efficient, great for real-time content-heavy Internet apps. 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 DBMS. A database engine is the principal software component that a DBMS uses to create, read, modify and delete data from a database. Its latest version offers considerable improvements in efficacy, reliability and usability. InnoDB offers the standard ACID-compliant transaction features, as well as referential integrity support. It is included by default in most binaries distributed by MySQL AB.