Varnish

Varnish Cache is a web accelerator also referred to as a caching HTTP reverse proxy. You can install it in front of any server that speaks the HTTP protocol and configure it to cache the contents. Varnish Cache is really, really fast and will boost your website's loading speed. One of the chief features of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which allows you to choose how incoming requests should be tackled.

Memcached

Memcached is a general-purpose memory object caching system for boosting the loading speed of 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 system uses a two-tier architecture. The Memcached memory caching system is employed by some of the most popular websites on the web and is supported by popular Content Management Systems like Joomla and WordPress.

Node.js

Node.js is a software platform for writing highly scalable network applications. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, asynchronous I/O model that makes it lightweight and efficient, perfect for real-time content-intensive 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 relational database management system. A storage engine is the underlying software component that a DBMS uses to create, retrieve, modify and delete data from a database. The latest edition of InnoDB offers significant improvements in efficacy, dependability and functionality. InnoDB offers the standard ACID database transaction properties, as well as foreign key support. It is included as standard in most binary distributions from MySQL AB.