[|] Answer [|]
<u><em>The feeling or certainty that you have the mindset and / or power to accomplish or do something</em></u>
[|] Explanation [|]
When having confidence, you believe that you have it in yourself to accomplish and follow through with something. Whether that something be climbing a mountain, learning how to ride a bike, figuring out how to drive, anything. Anything that you do, you can have confidence in yourself.
A more cliché version of having confidence is the term "<u><em>Believe in yourself.</em></u>" When having confidence, you believe in yourself. You feel like you can rely on someone (even yourself), and you believe that you / they can do it, whatever "it" is. You feel certain about a particular subject or event.
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