Option vs Result

OptVsRes.txt

I think it's quite easy.. Option is for functions that may or may not return a value (say, a string search may find something or may not find something). So, both return values are valid and expected in your program.

Result, as is is shown by the Err enum, is for functions that are expected to succeed (thus, Ok()), but may fail and this has to be catched. Example: Opening a connection to some other server would generally be expected to work but of course can fail.