title: Can the hash of 2 different inputs be the same?
body: <p>According to my understanding, Hashing is a process of producing a unique fixed length (let's assume 64bit) output to an input of ANY length. (correct me if am wrong)</p>
  
  <p>So if I take all the (x) possible 64bit hash values that a hash function can produce and append a 0 or 1 at the end of it. I get a list of size 2x (where each hash is 65bit long).</p>
  
  <p>If I give all the 2x combinations as the input to the same hash function, how can it generate a unique hash for all the inputs?</p>