Can you tell me the difference between result, consequence, outcome and the use of each words?
All three words share a common core concept: what comes after an event or action. What is unique to each word is connotation.
Consequence almost always carries a suggestion of something potentially or actually negative. One would not expect some one to say, "as a consequence of your work ethic over the past month, you are getting a promotion!" One does not generally want to "face the consequences" as it's not likely to be a good thing.
Result and outcome are more alike, in that there is no implied negativity.
Result is more commonly used in regular conversation, and is most appropriate in referring to what are the effects of some actions. So "the result of your diligent study was a good grade on the test."
Outcome is most commonly used in technical settings, and has a more specific meaning relating to the final observed results in a study or at the end of an observational period. For instance: "placing an IV immediately upon admittance to the ER often results in shorter ER stays, but is not necessarily correlated with positive patient outcomes based upon primary provider follow-up and patient surveys."
As another example, the result of raising prices might be higher profit margins, but the outcome of a pricing strategy may be less profit from a reduced number of sales.
When in doubt, use result because it implies the least. When you want to imply something negative, or potentially negative, use consequence. Reserve outcome for formal, technical discussions.