When you write a file to your computer, you are the one that determines what goes into it. The file isn't encrypted when you save it, but that doesn't mean that what you write to it can't be encrypted. Try running this code:
open to write 1 , "testing.dat"
write byte 1 , 5 : rem how many poops my dog did today
write byte 1 , 42 : rem the meaning of life
write byte 1 , 20 : rem how much cooler I am in %
write byte 1 , 12 : rem apples
close file 1
Then open up the file "testing.dat". You'll see a mess of weird characters. The data is still there though, and you can read it in again with this:
open to read 1 , "testing.dat"
read byte 1 , poops
read byte 1 , meaningoflife
read byte 1 , coolerthanyou
read byte 1 , apples
close file 1
Those aren't the only commands you can use, here's a list of the type of data you can write to a file:
write byte
write word
write long
write float
write string
write fileblock
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