[yuhe00]

Most of the work in programming is in describing (in very strict and pendantic terms) how different systems interact with each other and how the data flows from one end to another. The actual work of moving the data and doing all the calculations is handled by machines. In that sense, the work done in programming is designing and integrating systems, not the execution of it. In your analogy, installing a shelf would be more like installing Photoshop (which we can presumably agree is actually simpler than installing a shelf). Most people do not design their own shelf, select the most appropriate fasteners, source raw materials and send it to manufacturing to be mass-produced. A shelf is also a relatively simple piece of furniture. What about a desk-drawer or a closet? Sure, you can buy the raw materials and power tools at any hardware store, but is it trivial for anyone to actually design and build usable (and desirable) furniture from pieces of plywood?