Q codes and abbreviations are very useful when communicating with CW (Morse code) particularly if you are communicating with someone who is not fluent in English. The Q codes and abbreviations given here are used internationally. These codes and abbreviations also save time; it is quicker to send "QRM" than "I am getting interference from other stations". They are also used when communicating by standard telephony (talking into a microphone); the same advantages exist. Please don't worry about learning all these codes, with time you will come to know and use them all, but for the purposes of the exam I have suggested which ones you should memorise.

QRA     What is the name or callsign of your station?
QRB     How far approximately are you from my station?
QRD     Where are you bound and where are you from
QRG     Will you tell me my exact frequency?
QRH     Does my frequency vary?
QRK     What is the readability of my signals(l-5)?
QRL     Are you busy?
QRM     Are you being interfered with? - Man-made interference
QRN     Are you troubled by static? - Atmospheric noise
QRT     "on-the-side"
QRU     Have you anything for me?
QRV     Are you ready?
QRW     Shall I tell that you are calling him on channel ?
QRX     "off-the-air"
QRY     What is my turn?
QRZ     Who is calling me?
QSA     What is the strength of my signals (1-5)?
QSB     Is my signal fading?
QSL     Can you acknowledge receipt? - Acknowledged
QSO     Conversation on the air.
QSW     Do you wish to transmit on this frequency?
QSX     Will you listen to on channel?
QSY     Shall I change to another frequency? - Changing frequency
QTE     What is my bearing from you?
QTH     What is your position in latitude and longitude? - location
QTI     What is your course?
QTJ     What is your speed?
QTL     What is your heading?
QTK     What is the exact time?
QTU     What are the hours during which your station is on air?
QTX     Will you keep your station open for further transmissons?
QUA     Have you news of...?
QUD     Have you received the urgent signal sent by...?
QUF     Have you received the distress signal sent by?