Hey Hey,

I've seen a few people posting lately and throwing around the terms 'Open Source', 'Closed Source' and 'Commercial'... I think it's important to identify the differences in these models.. (There's also Shared Source (I.E. Microsoft) but that's a whole other can of worms).

Open Source: This means that the source code to the software is available for in-house modification. That's what the 'Open Source Community' drives for... open modification and contribution of those modifications. Open Source, however, does not automatically guarentee that the software is free. I have see a few, not many, but a few projects where when you purchase the product the product you receive both the binary and the source. Not so you can distribute it, that would violate the license, but so you can make custom modifications for in house use. You have to remember that there are other open source liscensing structures other than the GPL.

Closed Source: This usually means a binary is available for distrobution only, there is no available source code, even if you purchase the product. This however, doesn't mean you have to purchase the product... Look at freeware, a good chunk of it is closed source, but distributed freely.. Again there are a variety of licenses available.

Commercial: This means they're selling the product, however just because something is Closed Source, doens't mean it's now a Commercial product... Both open source and closed source can be commercial products, but they could also not be commercial products.

I just thought that maybe some clarification was necessary there... Primary because everyone thinks that because Nessus has gone closed source, it is now a commerical app... It's still being distributed free, just only in a binary format.

Peace,
HT