Coursera: Startup Engineering (Stanford) by Balaji S. Srinivasan and Vijay S. Pande

On code's generality:

As we will see, software is the most general product imaginable. Soft- ware encompasses ideas (news, blogs), entertainment (music, movies), material goods (3D printing, CAD/CAM), communications (email, social networks, mobile phones), transportation (electric cars, self-driving cars), energy (smart grids, adaptive braking), medicine (genomics, EHRs), and more besides. This is why Software is Eating the World and all products and professions - from watches, maps, and phones to travel agencies, librarians, and photographers - are being reimagined by software. This is also why it’s feasible for Google to go from a search engine into maps or from Amazon to go from a bookstore to a server farm: software engineering skills are highly portable, more so than virtually any other skill save mathematics.

On business:

An idea is not a mockup
A mockup is not a prototype
A prototype is not a program
A program is not a product
A product is not a business
And a business is not profits

(And, he wryly notes, profits are not happiness)

Example stack:

(Image credit: Startup Engineering by Balaji S. Srinivasan, Vijay S. Pande)