Varnish

Varnish Cache is a web application accelerator also known as an HTTP accelerator. You can install it in front of any server that speaks the HTTP protocol and configure it to cache the content. Varnish Cache is very, very fast and will boost the loading speed of your website. One of the essential virtues of Varnish Cache is the flexibility of its configuration language, VCL, which allows you to define how incoming requests should be tackled.

Memcached

Memcached is a general-purpose distributed memory caching system for boosting the load speed of 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 caching system uses a two-tier architecture. The Memcached system is employed by some of the most traffic-heavy websites on the web and is supported by famous CMSs like Joomla and WordPress.

Node.js

Node.js is a software platform for writing highly scalable network apps. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, non-blocking input/output model that makes it lightweight and efficient, great for real-time content-heavy network 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 database management system. A database engine is the primary software component that a DBMS uses to create, read, update and delete data from a database. The latest edition of InnoDB features substantial improvements in efficacy, reliability and usability. InnoDB offers the standard ACID-compliant database transaction features, as well as foreign key support. It is included by default in most binaries distributed by MySQL AB.