A system in a collection of component working together or are related.
Example of system is a graph:data structurewhere node and edges describe how data is related.NOTE: you can create your own system ,for example:what makes a good writer.I could describe a write with a good measure of quality and quantity of 80% a good writer.
A system can be inadequate if it not does met requirement,or incorrect in the blueprint (class in programming)If you create or use such system,your code will give inaccurate results.The system requirement could follow a conventional standard to keep everything compatable with allthe components within the system.
Non standard systems are those without convential implemention/algorithm.They are prone to break easy.In cryptography,standards to make sure everything is keep secret at the most basic level.
History is the background which a good system is built on.
Try this look up:NumberPhile and describe number theory in your own words.