asp.net web api - advantages of webapi in comparison with web services and wcf -

i asked in interview following question webapi

why need webapi?

i told "the services created in webapi can used across wide range of devices laptop, desktop, tablet , mobiles."

then interviewer asked why cannot done using web services , wcf?

i don't know answer.

can let me know answer.

copying title of question search engine yielded following link.

wcf , asp.net web api

wcf microsoft’s unified programming model building service-oriented applications. enables developers build secure, reliable, transacted solutions integrate across platforms , interoperate existing investments. (asp.net web api) framework makes easy build http services reach broad range of clients, including browsers , mobile devices. asp.net web api ideal platform building restful applications on .net framework.

there table detailing when should use which.