Almost as important as the quality of a piece of software—perhaps even more important—is the way it introduces itself. Just as we appreciate courtesy from people we meet, whether in person or online, so do we expect good manners from the software we load.

Software is a kind of conversation between the programmer and the user. The user is saying, “I want to do this.” The programmer is saying, “Here’s how I think you should do it.” Depending on how the programmer makes his point, the user either continues the conversation or walks away.

Good conversations start with good introductions. Consider all the different ways that software invites itself onto your computer:

Boxware. You go to Office Depot or Staples. You find the software shelf and select the product. You buy it, open the box, and remove an installation manual and a disc. You install the program on your computer. If the program is convenient to use, you keep it. If not, you return it and get a refund.

But check the warranty. When Vista first came out, even before the critical reviews began to pile up, I was in an Office Depot considering the purchase. But on the box was a store-applied warning label. “Non-refundable, even if it doesn’t work.” Wow. Just like a round-trip ticket on the Titanic. I put the box back on the shelf.

Freeware. You’re browsing online: Lifehacker posts a list of the five best downloadables in a specific category. You download the one that has the best reviews, install it, try it. It works, you’re happy, you keep it.

Once in a while you wonder how the authors of the program make any money. If you visit their website, you see they have other products, some free, some for sale. Maybe you buy one, maybe not.

Communityware. You’re looking for a specific utility. Google points you to an open-source community that has developed a set of tools to provide that functionality. It is free for you to download and use. But you are not allowed to market the product or any part of it in anything else you do. Not a problem if all you want to do is use the program. Audacity is a good example.

Donateware. Maximum PC has an article recommending free downloadable software. Like freeware, no payment is required. On the program itself, as well as on the website, is a button to click if you want to donate money for further development of the program. Calibre is supported by donations.

Upgradeware. Gizmodo posts a list of essential utilities. They’re all free to use, no obligation attached. You download a few, they make your work easier, you keep them. On the program itself, as well as on the website, is a button to click if you want to upgrade to the professional version of the program, which has more features. CCleaner is upgradeware.

Trialware. You need to do some serious photo-manipulation. You don’t need to Google for recommendations, you already know what you want. You go to the Adobe website and download Photoshop Extended CS6. You are free to use it and all of its features for 30 days. At the end of 30 days, the trial period expires and the product stops working. You have found it a powerful and essential tool, so you buy it to keep using it.

Shareware. The program is free to download and use. If you like it, you pay for it. Simple in concept, popular with users. Hardly anybody does it anymore.

Doomware. The first 10 levels of the game are free; each level introduces you to a new part of the whole game. You can stop at the 10th level, but if you’re hooked, you rush to pay for the full game. This is how John Carmack became a millionaire almost overnight.

Demoware. PCWorld runs an article reviewing a dozen products in a critical category. You download one that looks like it will do the job. It processes all 22 pages of the file and puts a watermark on every page, making the results completely useless to you. To remove the watermark, you have to buy the program.

Crippleware. So you go back to the article in PCWorld and download the next recommended program. It looks at all 22 pages, processes three, and tells you that the demo version will only process 6% of the job. You have to buy the full program to process a whole file.

Or worse, the actual feature you want to explore isn’t available in the so-called “trial version.” The downloaded version is so completely crippled, it’s little more than a demonstration of the user interface, and you can’t really test if it works.

Promiseware. PC Magazine’s website tells you that you should clean your registry and points you to several programs that should do the job. You download one. It looks at your registry and identifies 643 invalid or incorrect entries. It promises to fix them… right after you pay for the program.

Nagware. Another recommended download, but this one makes you look at a splash screen for 30 seconds that promises to go away after you register. Periodically while using the program, the program interrupts itself to remind you that this is an unregistered copy, not yet paid for, and there are a whole lot of extra features that you will be able to use as soon as you register. The nag screen pops up every time you open the program, close it, hit save, or just at random.

Cheatware. You install a program that promises to reimage all the pieces of your operating system and restore it to cherry condition. You run it and it gives you a list of all the fixes it can do—as soon as you pay for the program. Meanwhile, it has reset the homepage on your browser, reset your default search engine to one loaded with ads, and also installs three new ad-supported toolbars.

Preview-ware. You download and use a fully functional release candidate or preview edition that allows you to experience the program before it actually ships. Your preview expires when the real software ships.

This is how Microsoft is currently introducing users to Windows 8 and Office 2013. The company is confident that users of the preview editions will enjoy the new features so much that they will generate positive word of mouth before the final version ships and happily pay for it when it does.

Coming back to the idea that software is a conversation between the user and the programmer, and that good conversations start with good first impressions, think about all the different introductory experiences listed above. Which ones are going to inspire you to reach for your bank card and which ones are going to have you clicking on Revo Uninstaller?

Crippleware, Demoware and Promiseware disrespect the user. They’re saying, “I’m afraid you won’t pay me, I don’t trust you.” Cheatware is even worse, saying “Your computer is for me to use, not you. It’s a place where I get to sell ad space.” And Nagware doesn’t care about your workflow; it reserves the right to interrupt you and make you wait to resume working.

Take a moment to imagine the authors of that software behaving that way in person. You’d invite those people out so fast that Einstein would have to rethink the speed of light.

I prefer the message that the Photoshop trial versions and Microsoft preview editions speak: “I want to be your partner. We’re in this together; I want you to be as productive as possible with the best tools I can provide. So I’ll work for you for free, long enough for you to become informed enough about my skills that you’ll hire me full time.”

Just like people, software gets only one chance to make a first impression. Just like human beings, software is a relationship. And just like human beings, good manners go a long way. Bad manners do not.

What do you think?

David Gerrold is the author of over 50 books, several hundred articles and columns, and over a dozen television episodes, including the famous “Star Trek” episode, “The Trouble with Tribbles.” He is also an authority on computer software and programming, and takes a broad view of the evolution of advanced technologies. Readers may remember Gerrold from the Computer Language Magazine forum on CompuServe, where he was a frequent and prolific contributor in the 1990s.