Tax deed sale is the sale of real estate encumbered by the unpaid real estate taxes.
Tax lien sale is a sale of any assets of the taxpayer which could be personal property or real estate to satisfy the tax lien.
The priority of a tax lien sale could be inferior to a mortgage. But the priority of a tax deed sale is almost always first in line.
A tax deed is when you fail to pay your county property taxes, a tax deed is issued and auction held.
A tax lien is typically say the IRS who can lien your house in a priority just like a mortgage would; and can/will foreclose in only certain circumstances