Courses essentially cover a programming language or some other computing technology such as AJAX. On the other hand, tutorials cover a concept/idea that is made using a combination of multiple programming languages/computing technologies.
Yes. Absolutely. This is the aim of CodeGuage — to provide free computer science education.
No. We don't want to place multiple hurdles before you can begin learning.
Yes. We are adding more and more content to all the listed tutorials, and even further improving the current ones to address more and more questions of the novice reader.