Local Time = Local time according to the TIMEZONE setting.
UTC = Coordinated Universal Time.
UTC is widely used by navigators that will be passing throughout many time zones. I.E. an Airliner flying from New York to Paris will use UTC time when talking to the control tower in Paris as well as New York. This puts everyone involved in the same time zone for less confusion.
Note: With Hugo UTC is derived from the GPS SV atomic clock. As such this time tends to be very accurate. Depending other factors the time should never be off more then a few seconds.
More info on UTC:
International basis of civil and scientific time. Implemented in 1964,
UTC is widely broadcast by precisely coordinated radio signals; these radio
time signals ultimately furnish the basis for the setting of all public
and private clocks. UTC has been obtained from atomic clocks as of
Jan 1, 1972.