Indictable offences refer to serious crimes that require a grand jury to determine if there is enough evidence to charge the defendant, and can potentially result in felony charges and jail time if convicted. They include crimes like murder, rape, kidnapping, robbery, arson and fraud. Indictable offences require a trial by judge and jury, carry more serious fines and potential jail time of up to life imprisonment compared to summary offences which are less serious and can be punished by a maximum of six months imprisonment and a $2000 fine if convicted.