There a lot of abbreviations and codes that are used by Amateurs when using morse code (CW) and datamodes. We have a list of internationally recognised abbreviations which will enable people with a common knowledge to communicate

AbbreviationDefinition
73Best Regards
88Love and Kisses
ABTAbout
AGNAgain
ANTAntenna
B4Before
BKBreak (to pause transmission of a message)
CFMConfirm
CLGCalling
CLSClose / Closing
CONDXConditions
CQCalling Any Station
CSCallsign
CUAGNSee you Again
CULSee you Later
CUZBecause
CWContinous Wave
CXConditions
DEFrom
DNDown
DRDear
DXDistance (sometimes refers to long distance contacts)
ESAnd
FBFine Business
FERFor
FMFrom
FREQFrequency
GAGood Afternoon / Go Ahead
GBGoodbye
GDGood Day
GEGood Evening
GMGood Morning
GNDGround (Ground Potential)
GUDGood
HIThe Morse Laugh or High
HPEHope
HRHere
HVHave
HWHow
INFOInformation
LIDPoor Operator
NNo
NILNothing
NRNumber
NWNow
OMOld Man (Any Male Amateur Radio Operator is OM)
OOOfficial Observer
OPOperator
PSEPlease
PWRPower
RReceived
RCDReceived
RCVRReceiver
REFRefer to, Reference, Referring to
RFIRadio Frequency Interference
RIGStation Equipment
RPT / RPRTRepeat or Report (Depending on Context)
RPRTReport
RTTYRadioteletype
RXReceiver / Received
SIGSignal
SIGSSignals
SKEDSchedule
SNSoon
SMSShort Message Service
SRISorry
SSBSingle Side Band
STNStation
TZero
TEMPTemperature
TFCTraffic
TMWTomorrow
TNXThanks
TTThat
TUThank You
TVITelevision Interference
TXTransmitter / Transmission
TXTTest
UYou
URYou
URSYours
VYVery
WWatts
WIDWith
WKDWorked
WLWill
WPMWords per Minute
WUDWould
WXWeather
XMTRTransmitter
XYLWife
YLYoung Lady (Used for any female)
YRSYears