https://help.tallysolutions.com/docs/te9rel64/Voucher_Entry/Accounting_Vouchers/Sales_Entry.htm

Introduction Sales Voucher

Sales Voucher is used to record the Sales transactions of the company. You can pass an entry using the Voucher mode or the Invoice mode where the calculations can be automated and the transactions can be fed into the system easily.

Click on the following links for more:

Creating a Sales Entry

Configuring a Sales Invoice

Configuring a Invoice

Printing a Sales Invoice

Allow Income Accounts in Sales Vouchers