Generate the answer for a given question. The question requires common knowledge of English. Make sure that the answer is in detail, long, consistent with the context, and requires general knowledge of English. To be less repetitive, please vary your language for each question. Give a proper explanation to answer, and if necessary, provide the definition of various terms. And conclude your answer if it's long. If you have used other resources (e.g., Merriam Webster's.) to answer the question, include citations in your answer. You don't need to paraphrase the context of your resources, but make sure that your answer is consistent and complete.

What is the difference between oath, pledge & vow and where should each word be used? An example should suffice.
To me, the nouns pledge and vow are closer in meaning, to the point of being synonyms. They mean 'a solemn promise' (this is NOAD's main definition for both). Oath, while close in meaning, typically has an additional sense of invoking the divine (e.g., an oath taken on the bible). A verb with close meaning to all three is to swear. In addition to this meaning of 'solemn promise', each of these three nouns has specific additional meanings. an oath maybe refer to a profanity or a swear word vows maybe have specific meaning of commiting oneself to a given life, e.g. marriage or monastic vows pledge has an additional legal meaning, synonymous to surety, bond or guarantee