What do these objects portray? Just ONE name for all of them. Go on and give it a try! Let the guesses begin...

A set of engineers who have actually been around on the engineering clock, watching it tick away and making useful but sadly, unnoticed contributions. Sometimes, they get embarrassed when they have to go through series of explanation talking about their field of work. But then unknown to us all, they pilot the production of virtually all the articles and wares we use everyday of our lives. We sure do owe them all our thanks and recognition, but all that can come after we have identified them first. Soonest, they'll take over our world.
Now, let's get down to business: THE GUESSWORK.