Tax Increment Financing (TIF) is the process of recovering invested funds by "capturing" the increased taxes from a parcel of property.  It works something like this:

1) A person, group or government spends money on some project that benefits the public ( building roads, cleaning a polluted property, etc ) under the auspices of a government board.

2) The investment of that money causes the surrounding property to become more valuable, or to attract other investments.  ( Developers build expensive buildings on the land. )

3) Let's say a parcel used to pay $1,000 in taxes and now pays $11,000.  The new $10,000 is the "TIF".

4) The authorizing government board takes the TIF and uses it to reimburse those who made the original investment.  Local units of government keep collecting the same $1,000 they have been getting for years.

5) After the investment is fully reimbursed, those local units of government start collecting the full $11,000 in taxes.