Alexa is a competitor intelligence and website analytics software that provides actionable SEO insights based on a sample of data from the web. Alexa enables users to view audience demographics, engagement, traffic trends, keyword research, traffic sources, and website comparisons.
jQuery is a cross-platform JavaScript library designed to simplify the client-side scripting of HTML. It is free, open-source software using the permissive MIT License. Web analysis indicates that it is the most widely deployed JavaScript library by a large margin.
PHP: Hypertext Preprocessor is a server-side scripting language designed for Web development, but also used as a general-purpose programming language. PHP code may be embedded into HTML code, or it can be used in combination with various web template systems, web content management systems, and web frameworks.