Upon your passing, your assets that pass on to your heirs will be valued at a base value equal to the appraised value at the time of your passing so if they sell the assets at base value, they don't have to pay tax - essentially your estate is tax free up to ~$11 millions.Ok....iv no idea what that is...dont want to know either.
The only exception is regular IRA/401K, it will be considered as ordinary income to your heirs and will be taxed accordingly.