Wills are a very good source of information. They can give the home address and occupation of the testator. The names of the beneficiaries and some times their address and occupation. All of the members of the immediate family may be named.
They may have the details of the property and goods of the testator and the names of the executors and witnesses to the will who may also be related to the testator.
Wills can therefore give a complete picture of a family,how they lived and evidence of their wealth and social status.
For those of you searching for information on wills in Northern Ireland may just be lucky and find your ancestors in the online wills calendars at Proni.Try different searches when looking at the data bases,try full names,or surnames only with the name of a townland.