What is abstraction in computing? Give an example of how it works.
Abstraction is when functionality of some parts of a system are hidden from other parts of the system. For example, when a driver starts his car - he does not need to know about the inner workings of a combustion engine, he simply turns his key and the ignition starts. In this example the engines functionality is hidden from the driver.
If you would like to explain to someone how your day has been, which tense would you use? What are the three tenses?
I would speak in the past tense. The 3 tenses are past, present and future.
What is a pre-processor directive in C# and how would you use one?
A pre-processor directive indicates code that should be executed before compilation begins. We indicate pre-processor directives by following a line of white space with a # character.