Hi guys, starting to understand Solidworks and i just got problem with understanding standard wizard hole using UNC and UNF.

i've been practicing Solidworks and just started 3 days ago through self-learning via (youtube and websites tutorials)  and i just encounter a description of "6-32 UNF-2 or Unified National Fine (from google) "which should be the standard size of the hole for thread if i got it correct however i still don't understand.

This 6-32 UNF-2, can you explain it to me because i tried to search it on google but
it would be best if I ask some experts rather than guessing on my own to avoid inaccurate information.
many thanks!

my Questions are:
What 6-32 mean is it 6/32 size or is it
6 stand for 6 mm/inc and 32 means the number of thread cycle

and what does -2 next to UNF stand for?

Picture #8

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