[daniel_reetz]

My domain is mechanical engineering. In my discipline, the Parker O-Ring catalog or the Omega Sensors catalog are basically textbooks which teach you how to specify and select seals and sensors. They create experts, and in the process, create sales and users.

The really outstanding trick of these catalogs is they also work as shortcuts. You can go to a table and pick an O-ring with very little expertise, and it will tell you the groove size, corner radius, etc.

In short, when you're documenting tools or engineering components, and your audience is tool users, teaching is a highly effective approach.

[HeyLaughingBoy]

My first job out of college was mostly designing hardware and writing product user manuals for our industrial I/O interfaces. I agree: those massive Omega catalogs were like textbooks to me. I learned an enormous amount about sensors and how to interface to them and that knowledge is still useful decades later.

One thing missing in this discussion is that the audience is important. Omega Sensor catalogs are great for design engineers. OTOH, you can find a lot of the same products in a McMaster-Carr catalog, but their focus is on the buyer and they are well optimized to sell to that person.