Various tax systems grant a tax exemption to certain organizations, persons, income, property or other items taxable under the system. Tax exemption may also refer to a personal allowance or specific monetary exemption which may be claimed by an individual to reduce taxable income under some systems. Tax exempt status may provide a potential taxpayer complete relief from tax, tax at a reduced rate, or tax on only a portion of the items subject to tax. Examples include exemption of charitable organizations from property taxes and income taxes, exemptions provided to veterans, and exemptions under cross-border or multi-jurisdictional principles. Tax exemption generally refers to a statutory exception to a general rule rather than the mere absence of taxation in particular circumstances (i.e., an exclusion). Tax exemption also generally refers to removal from taxation of a particular item or class rather than a reduction of taxable items by way of deduction of other items (i.e., a deduction). Tax exemptions may theoretically be granted at any governmental level that imposes taxation, though in some broader systems restraints are imposed on such exemptions by lower tier governmental units.