Tally Definition Language (TDL) is the development language of Tally. ERP 9. TDL is developed to provide the user with the flexibility and power to extend the default capabilities of Tally, and integrate them with the external applications. TDL provides a development platform for the user.

With TDL, tally.Erp9/ TallyPrime can be customized to add almost any functionality which is not available in tally by default.

Using the capabilities of TDL, we can achieve the following

1. Integration of Data from a different Application/Web Apps with the Tally via access to API.
2. Bulk share invoices, vouchers, reports via Email or Whatsapp
3. Invoice Printing Customization, Payment Advice Printing, Voucher Printing, etc. in user desired pre-preprinted or plain formats
4. Various Columnar reports like Batchwise Itemwise Reports, ItemwisePartywise Outward and Inward Movement Analysis
5. Various security related controls like Voucher Type wise Entry Control, control the table of selection based on users like Sales persons can view only Debtors Ledgers, etc.
6. Labels and Bar Code Printing
7. Auto creation of Masters/ Transactions as required