Hsc is not a tool for beginners. It does not make html easier. It only makes it a bit less painful and brain-damaged - that's all. Therefor, these documents assume that you are already familiar with html. There exist several sources for beginners, and this won't be page #1876545 which lists these sources.
The user is expected to have already worked with some macro language before.
If you want to utilize the project management capabilities, you should also know how to work with make and write your own Makefiles. As it does not make much sense to use hsc without it, this probably is a must.
For several other advanced topics, it is required to have some experiences with any programming language. Rexx is fully sufficient for these task, and most examples and some supporting stuff is written in this language.
As hsc is a CLI-only tool, any knowledge of how to work with mouse and icons is not required.
Please note that I'm quite serious about all that. As I don't get paid for every new user, there is no need for me to have as many people as possible using this program.
Actually I do not care if you try to use it, find out you can not cope with it, scream out "Dammit, I'm a looser!" and jump out of the window from the 27th floor. But I start caring about as soon as you do not jump out of the window and instead send me bloody emails with silly questions.
So those who now say "Fine, I always wanted to learn how to write Makefiles" should consider looking for some other tool or prepare themselves for jumping out of the window.
Memory: Well, this mostly depends on your input-data. To process reasonable sized pages, about 300K of free ram should be enough. For large pages and projects using loads of documents, this can increase to 1MB or even more, so your machine should have at least 2MB of memory.
Stack: A stack value of 12 KB usually should be sufficient; at least, this worked for these documents.
AmigaOS and CPU: Basically, it works on an A2000 with AmigaOS 2.04 and a plain 68000, but as this isn't much fun, the binaries are compiled for 68020. As hsc is not one of the fastest, a 68040 is recommended.