Praise be to God, in Islām a number of behaviours have been forbidden for our benefit and because they have been commanded by Him. Below you will find a summary of those behaviours, and In Shā Allāh, if God has willed it, sources will be added in due course.
Eating food which is not halal
Gambling
Shirk
Killing an innocent without justification
Charging or receiving interest, and usury
Sex outside of marriage (Zinā)
Accusing chaste women of sex outside of marriage
Using drugs and alcohol
Beating women
Backbiting (Ghībah)
Bearing false testimony
Disobeying parents
(the exception being that they try to take you away from Allāh and His teachings)
Sodomy
Stealing
Stinginess and not paying proper compensation for work done or a service
Celebrating birthdays and other ‘holidays’ that aren’t Islamic
Oppressing people
Imitating non-believers
We are called to separate ourselves from those who disbelieve, therefore we shouldn’t imitate them in how they look or dress, or their customs and practices.