Varnish

Varnish Cache is a web application accelerator also referred to as an HTTP accelerator. You can install it in front of any web server that speaks the HTTP protocol and configure it to cache the content. Varnish Cache is really, really fast and will boost the loading speed of your site. One of the chief strengths of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to define how incoming requests should be dealt with.

Memcached

Memcached is a generic memory object caching system for speeding up dynamic database-driven web 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 distributed memory caching system uses a two-tier architecture. The Memcached distributed memory caching system is used by some of the most traffic-intensive websites on the World Wide Web and is supported by famous CMSs like Joomla and WordPress.

Node.js

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

InnoDB

InnoDB is the default database engine for the MySQL open-source database management system. A storage engine is the principal software component that a database management system uses to create, read, modify and delete data from a database. The latest release of InnoDB offers substantial improvements in efficacy, stability and usability. InnoDB provides the standard ACID-compliant transaction properties, along with foreign key support. It is included by default in most binaries distributed by MySQL AB.