What does “DISTRESS” signal mean?

FORMAT of RADIO Telephony distress call :-

Mayday (x3)
This is
Name (x3) / Call sign / MMSI no. of ship.
Radiotelephony distress message
Mayday
Name/ Call sign/ MMSI
Position
Nature of distress .

Type of assistance required any other information which might facilitate the rescue.

Format of NBDP distress call and message

MAYDAY
DE
CALL Sign
MAYDAY
Name/ Call Sign
Position
Nature of distress
Type of distress/ assistance required
Additional information that may facilitate rescue.
MASTER
NAME/ Call sign
Time (UTC)
NNNN