Property Tax is tax levied against real or personal property.
Property tax is usually quoted as so many dollars per $100 of assessed valuation or so many mills (.001 of a dollar) per dollar of valuation.
25 mills is $.025 per $1 of valuation. This can also be quoted as $25/$1,000 or $25 per $1,000 of valuation.
Property tax is calculated by multiplying the tax rate by the assessed value. For example, if a house has an assessed value of $50,000 then the tax at 25 mills is: $50,000 x .025 = $1,350.