When you choose to use an article in English, as with many other choices, you are deciding how you want the reader to react to the information you are presenting. There are a few "mechanical" rules concerned with the system, but many decisions must be made according to how you want the concept to be understood by the reader.
Some of the choices you must make are the following:
Is the noun countable or uncountable? Now try this exercise after reading the review.
Is the noun part of a specific pattern? We often find the following pattern: article + noun + of
Is the noun a common or proper noun?
Is the noun being used in a general or specific sense?
Is the noun known or unknown to the reader?
Only when you have answered these questions can you decide to use an article or not, and which one to use.