If you have a website, you are at least in the marketing business; rather, your website is a marketing tool, for good or bad. If your website has any features other than basic marketing (prices, times, list of products or services, location, etc), such as purchases, mailing lists, and other such things, then the product you are giving your customers is software. That is in addition to whatever your core business is about.

Someone mentioned a dentist. If his website includes anything interactive, then part of his product to you is software. It might be a stretch to say he is in the "software business", but he (or an employee or contractor) is definitely delivering a software product.

Peter Drucker in "Management: Tasks, Responsibilities, and Pratices" offers the following definition of business and its' key functions:

"Because the purpose of business is to create and keep a customer, the business enterprise has two--and only two--basic functions: marketing and innovation. Marketing and innovation produce results; all the rest are costs. Marketing is the distinguishing, unique function of the business."

If you accept his logic, which I do, then to be in business is to be in the marketing and innovation business.

Using a service does not mean you are "in" that business, any more then being in a shop does not mean you own that shop.

Marketers are in the marketing business. Programmers are in the programming business. Having a website that you use as a marketing tool doesn't make you a marketer, it means you use a product for marketing.

That is just shifting the blame. If you use a product for marketing, you are marketing. Yes, in general, "using a service" does not mean you are in that business. But if you ask your users to take part in this service or tool you are using, you are now providing that service.

Chairs in your office for your customers? You have taken on the responsibilities of being a host.

We can debate indirect services, such as electricity to run a website, and I would say that that line of discussion is pointless. I rely on my electric company, but my customers rely on my website, and the customers blame me, not the provider I chose to host this feature, not the electric company that provides power to the web services provider.

Remember that the customer does not care about your problems. They care about theirs, and they see you as their cause.

For starters, you're comparison is completely off with what Jason said. A business might need electricity, plumbing, or furniture to operate, but how are these the same as a website? Are you saying that a website is equal to a chair at your doctors clinic? Saying a website is the same as utilities and structural needs of a physical space is a bit irresponsible. Second, what does whatever 'software' tools you use or if you're a developer/engineer have to do with a company being in the software business? They're not mutually inclusive, nor exclusive for that matter.

Most businesses with a website are in the software business the same way most businesses with personnel that deals with clients are in the customer relations business and the same way most businesses with a product are in the marketing business. Using whatever tools you use to create a piece of software which you later put at your clients disposal automagically enters your company into the world of the software business. Granted most companies have simple websites that you don't really need to give much thought to after launch as a company, but that doesn't exempt you from the fact that you're offering a service based on software the moment you put that website up.

Calling an HTML page "software" is stretching the definition of software to its extreme though; it's not so much akin to suggesting that businesses with client-facing personnel are in the customer relations business as suggesting that their mere ability to field a question puts them in the business of education.

I'll buy the argument that operating an e-commerce facility so that customers' requirements being met and payments being received depends on some non-trivial lines of code have entered the software business though.

I'd say it's the other way around. If you're working on an industry that would benefit from "teaching" your customers a thing or two, and you go ahead and answer each and every question, you'd be in the education business. Wether you use something as simple as an HTML page or something as complex a Rails stack is of no consequence to the fact that the end user is still interacting with a computer, programs, and data.

Hell I've seen some programs back in the day which where made just to display a box of with text. That's software also. Boring, small and useless software, but software nonetheless. The Irc warez scene used to be full with these type of ridiculous programs, though at least some had awesome 8 bit music.

The difference is the customer is not affected by electricity/plumbing/furniture that the company is responsible. Customers are affected by the company's website, which is a type of software.

My dentist has some pretty crummy chairs in the waiting room. This certainly affects my visits to the dentist. My dentist is not in the furniture business. My dentist also has a crappy website. He is not in the software business.

Does your dentist have receptionist who takes care of appointments and generally treats you nicely while you wait? He's in the customer service business.

Does your dentist have his diplomas, fellowships, and awards on his shelf? He's in the marketing business.

Does your dentist work on your teeth and makes you suffer and withstand amazing pains? He's in the dentistry business.

Does your dentist have a website? He's in the software business, regardless of if the website is a simple website so you can find his phone number or if the website provides a way to check your appointment date (or some other service).

Of couse he isn't.

If the toilet or sinks in my restaurant don't work, the customer will hold me responsible. It a light is burned out or a chair is broken they will hold me responsible. I am still not in the plumbing, electricity, or furniture business.

Apparently every store in the world is in the construction business. Who knew?