Varnish

Varnish Cache is a web application accelerator also called as an HTTP accelerator. You can install it in front of any server that speaks HTTP and configure it to cache the contents. Varnish Cache is really, really fast and will speed up your site. One of the essential strengths of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to choose how incoming requests should be handled.

Memcached

Memcached is a generic memory object caching system for boosting the loading speed of dynamic database-powered sites. It is used to lower 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 two-tier architecture. The Memcached system is employed by some of the most regularly visited web sites on the World Wide Web and is supported by famous CMSs like Joomla and WordPress.

Node.js

Node.js is a software platform for writing scalable Internet applications. Written in JavaScript, Node.js uses an event-based, non-blocking I/O model that makes it lightweight and efficient, excellent for real-time content-heavy network apps. Node.js uses Google's V8 JavaScript engine, libUV, and several built-in libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source database management system. A storage engine is the principal software component that a DBMS uses to create, retrieve, modify and delete data from a database. Its latest release features considerable improvements in performance, stability and usability. InnoDB offers the standard ACID-compliant transaction attributes, along with foreign key support. InnoDB is included as standard in most binaries distributed by MySQL AB.