In Florida, probate is a court proceeding which administers a deceased person's estate. It may be done either testate--with a Will--or intestate--without a Will. The probate process is usually referred to as "administration" of the estate.
A "Will contest" is an action to challenge the valuidity of a Last Will and Testament. In Florida, perhaps the most common basis for challenging a Will is grounded on allegations of "undue Influence." Undue influence, such as would void a Will, has been defined to include over persuasion, coercion, or force that destroys or hampers the free agency and will power of the person making the Will.
In Florida, in order for a Will to be enforceable, it must be signed by the testator/testatrix in front of two witnesses.
Most often, contesting a Will in Florida, as in most states, is based on allegations of undue influence, fraud, duress, or mistake.