Advance payment is the payment (mostly partial payment) even before the goods or services are delivered (in this scenario the person making the payment must deduct TDS and pay it to the government).
Tax Deduction at Source (TDS) is applicable to advance payments. Unlike normal tax payments, TDS in advance payments shifts the onus of paying the tax to the person or company who is making the payment. The payer deducts TDS and deposits it with the government, and on a quarterly basis files returns for the paid TDS. Then, within a year, the payer issues a TDS certificate to the supplier (payee). When the payee is filing returns, the payee can cite TDS deducted by the payer, which needs to be adjusted in the returns.
Overview of Tax Deduction at Source
How do I calculate TDS on Advance Payments