Why is Iambic pentameter important in Shakespeare's works?
Shakespeare used Iambic pentameter to imitate the rhythm of natural speech, he wanted the language to flow. He also used the rhythm to create stresses of certain words so you could get the sense of what the character was trying to say. Shakespeare also used verse (Iambic pentameter) and prose ( natural dialogue) as a way to differentiate between his characters. Verse was usually (not always) reserved for characters of a higher status in regards to class, wealth, morality, etc and prose was for lower status characters.
What is Social Psychology?
Its the area of study in Psychology that looks at social interactions, observing social behaviours, how and why they happen and seeing how it becomes part of our society.
How has Greek Theatre influenced modern day theatre?
They say no story is original, same could be said for theatre and its techniques. One of the many things Greek Theatre gave us archetypes like the Hero/heroine, villain, lovers, etc, which can be found in Commedia d'ell arte, Melodrama and still can be seen in modern day Theatre and television.