If you wish to learn the programming languages and that too free of cost you are most welcome on the W3schools.com.
I have learned many languages like html, java, php etc from this website.
It consists of various examples for a specific topic so that the one can understand the concept very clearly. And the language used in the theoriotical part is also very easy.
One limitation I can point out is the webpage takes lot of time to load. However such websites are the need of the hour and W3schools.com is the platform to learn