What are the types of martyrdom, and is the martyr of work among them?

The questioner did not specify the type of work meant by "martyr of work," whether it is permissible or forbidden, nor the intention of its doer or the manner of death. If the work is forbidden, its doer dies as a disobedient person. If it is in the path of Allah, such as jihad and seeking knowledge, then he is a martyr. As for permissible work like trade, its doer becomes a martyr if he dies in one of the manners mentioned in previous fatwas.