Similarities: Both a conversation and public speaking can entertain a small group of people or a crowd by telling your story or answering questions.
Differences: Public speaking is endured by an audience or crowd, a conversation is with a small group of people, public speaking is written before and read formally and logically, a conversation is thoughts in the moment; informal.
Explanation:
Public speaking is speaking in front of a crowd of people in a formal manner, where as a conversation is with a group, or 1-2 people and usually informal.
