The rel attribute is defined by many in the technology world to be an explanation of the relationship that exists between a current and linked document. It is used only when the a href link exists since these two attributes and links are complementary to one another. For technology savvy professionals and people who handle this sort of thing every day, the rel attribute is quite simple to understand and implement. But for the typical layperson, a crash course on the subject is a good idea.
For one, an rel attribute is simple in theory yet complications can come up when someone unfamiliar with the rel attribute tries to establish HTML anchors or attempts to link CSS to HTML in some way where this attribute exists. Even with simple to follow instructions, sometimes average people with a little knowledge of href HTML and of online codes gets lost in the mix of what should occur for something to go smoothly. What could take a technology guru a few minutes to figure out could possibly take the typical non technology savvy person an entire day and then some.
For another, an rel attribute has a value and a purpose, and defining that value and understanding that purpose can take some time to learn and completely understand. Books on this very subject are purchased every day by people attempting to get what makes an rel attribute what it is and how it can work to make online functions simpler, and there exists a key reason for this. It is not that easy for just anyone to get, nor is establishing a link in HTML or in other facets of web technologies. There are complexities and the potential for problems always lurking around the corner.
That being said, the rel attribute is one of the simpler attributes that are used throughout the web, and so anyone needing more information on it could easily secure help in the form of an IT professional or a neighbor with an excellent background in computers and some web savvy. Not everyone fully understands every web attribute that is necessary for websites to function well, but enough people know about it that they can help out others completely lost on the subject. It is just a simple case of supply and demand, and for people entirely unfamiliar with these tasks they simply can find more knowledgeable people willing to help them out.