Varnish

Varnish Cache is a web accelerator also referred to as a caching HTTP reverse proxy. You can install it in front of any web server that speaks HTTP and configure it to cache the content. Varnish Cache is really, really fast and will improve the speed of your website. One of the important attributes of Varnish Cache is the flexibility of its configuration language, VCL, which permits you to choose how incoming requests should be handled.

Memcached

Memcached is a generic memory caching system for boosting the loading 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 memory caching system is employed by some of the most popular web sites on the Internet and is supported by famous CMSs like Joomla and WordPress.

Node.js

Node.js is a software system for building highly scalable Internet apps. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, asynchronous I/O model that makes it lightweight and effective, excellent for real-time content-heavy network apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of built-in libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source relational database management system. A database engine is the principal software component that a database management system uses to create, read, update and delete data from a database. Its latest edition features serious improvements in performance, stability and usability. InnoDB provides the standard ACID-compliant transaction features, along with referential integrity support. It is included as standard in most binary distributions from MySQL AB.