A Taxpayer Identification Number (TIN) is an identifying number used for tax purposes in the United States. It is also known as a Tax Identification Number or Federal Taxpayer Identification Number. A TIN may be assigned by the Social Security Administration or by the Internal Revenue Service (IRS).
Titanium nitride (N) (sometimes known as “Tinite” or “TiNite” or “TiN”) is an extremely hard ceramic material, often used as a coating on titanium alloys, steel, carbide, and aluminium components to improve the substrate's surface properties.