Some of them are acronyms and some are Brand Names. Drok is in the latter category.
If someone feels your question is dumb, they can scroll right past it.
Sometimes you might get tired of the same question over and over, when the answer is right there.
But then the search feature isn't that good. You can put a question in Google along with diysolarforum as a search parameter, too.
But, sometimes our answers are like trying to lead a horse to water, and they won't drink it.
Had one like that a while back, it took a bunch of back and forth, before the light bulb turned on for them.
Once it finally clicked, all was good. Plus someone else reading the exchange, might find their answer without asking it.