Cryptographic Hash function

Newbie at crypto & security. So excuse me if my question
is naive.

As per what I have read, a cryptographic hash function
always produces a fixed length string as output. Does this
mean that the output string will always be longer than the
input string? Because if not, then there will be collisions -
am I wrong?

If this the wrong forum for this kind of question, can someone
direct me to the right forum. Also I have other questions about
CA's & digital certificates for web servers.


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