The laws of software

There a a couple of laws the govern software. Let's review some of the most common, starting with my favorite coming from a big company.

Conway's Law
Basically this states that software architecture would mirror organizational boundaries. Not surprisingly so since teams optimize to reduce cross team dependencies. It can however be put to good use. If you want to ensure good boundaries in your architecture, mirror those in your organization. Anecdotally I have seen when client and server are in one team. Amazing how the API's become tailored for a specific client and generality goes out the door.

Moore's Law
Probably the most common, this law has to do with the projected growth in computing. Moore's law states that the number of transistors in CPU's would double every 2 years. This made scaling up very tempting and bought many system and engineers some time. Just add ram and bigger CPU's. Scaling out, FWIW is a much better approach but does require some re-architecting if not done from the get go.

Shannon's Law
Shannon's law covers the speed at which data can be transmitted over a specific medium keeping in mind the signal to noise rate. Hard to imagine this law having an impact in the era of 10 Gig-E networks, but does impact wireless and other transmission protocols.

Little's Law
Little's law has application in designing concurrent systems and the relationship between latency and throughput whether a message queue, thread pool or web server. Simple states that the concurrent processing is a function of the incoming transaction rate multiplied with the processing time for every transaction. Example, assuming a consistent web page visit, if you page loads times go up, the CPU usage goes up, which can increase the page load time...you get the idea.