Key words:

Casual (informal) speaking or writing
Speech
Concise
Level of formality
Precise
Revise
Formal speaking or writing
a) A formal talk or address delivered to an audience
b) How formal or informal you speak or write in different situations
c) To reconsider and alter a piece of writing to make it more efficient; it usually involves making big changes to something you are writing, unlike proofreading which only looks at spelling and grammar
d) Accurate
e) To the point
f) Speech or writing designed for school or work, free from mistakes, no slang included
g) Speech or writing designed for day to day interactions with family and friends, does not need to be "perfect"