According to the father of Artificial Intelligence, John McCarthy, it is “The science and engineering of making intelligent machines, especially intelligent computer programs”. Artificial Intelligence is a way of making a computer, a computer-controlled robot, or a software think intelligently, in the similar manner the intelligent humans think.
AI is accomplished by studying how human brain thinks, and how humans learn, decide, and work while trying to solve a problem, and then using the outcomes of this study as a basis of developing intelligent software and systems
A simple example of Artificial Intelligence and Machine learning in action is Facebook’s use of Facial Recognition. When you upload a photo to Facebook, Artificial Intelligence enables it to make a recommendation on who to tag in that photo. Machine Learning comes into play as Facebook learns over time, due to more tagged photos of an identified friend, to identify an individual with more certainty.

Instead of a designer deciding on layout, colors, photos, and photo sizes, the software platform automatically analyzes all the input and recommends design elements to the user. Using image recognition techniques, basic photo editing like cropping is automated, and an AI makes design recommendations for the pages. Using photos already in the client’s database (and the metadata attached to those photos), the AI–which, again, is layered into Adobe’s CMS–makes recommendations on elements to include and customizations for the designer to make.

Artificial intelligence is an area of computer science which deal with creation of machines or software , which have the mind like human , which can understand and can react on different situation and which can develop it self.
Best example of Artificial intelligence in web applications is myraah.io.
Using AI in web applications we can make such software or applications which can deal with complex problems and find the solution in a more human-like fashion. one of the simplest example of this is the chess software which can be played by computers .
Using Artificial intelligence we can build such tools which can build web site itself and then keep enhancing thing accordingly from data it gather from different available sources and how the site is being used . One such example available in todays world is The Grid , It is the first artificially intelligent website-design tool, which develop website itself by the data user give it and afterwards it keep enhancing itself accordingly and produce result which can be efficiently present to the user on the Web.