They are and they aren't. First, you must have internet access on your job site, where you are working because that is where you will need them - not back at the office. Second, even if you do have internet access, you still cannot print them out or copy and paste a section of them into an email.

That is why many of us are here looking for pdf copies. I can use them anywhere. I generally don't have internet access on the job site at all, or it is very poor and sporadic.