Proforma invoice nothing but the invoice is recived before 
sending material for advance payment.

invoice is nothing but the invoice send with 
material.payemnt for this materail will give after 
suitablity.

Proforma Invoice : Preparing the bill from the seller to 
the buyer for the payment for their materials received. 

Invoice : Invoice is an document received from the sellers 
to the buyers including all the details of the -product, 
quantity, price etc.

When seller sends quotation to te buyer about the 
quantities and the tentative prices at which buyer can buy 
is called Performa Invoice.

When buyer accepts to buy the quantities at specified 
prices then the deal is called Invoice.

Invoices : Usually Invoices are two types 

Proforma Invoice : Requesting for a payment for the 
particular material where the buyer is suppose to buy. 

Commercial Invoices: Commercial Invoices is nothing but tax 
invoice, tax invoice is raised after receiving the amount 
from the buyer for his material, requesting the buyer to 
issue CST/VAT forms to the seller.  

Both the invoices are raised by the seller here.

Pro Forma Invoice:  This Pro-forma invoice is one which is 
sent before the commercial Invoice(original invoice) to 
receive advance payment from buyer. The seller will not 
record this as 'Account Receivable' in his account  and 
buyer will not record it as 'Accounts Payable'in his 
account. This is not true invoice.

Invoice" This is true invoice where in  the seller and 
buyer will record in their 'Accounts Receivable section' 
and 'Accounts Payable Section'. Payment will be done once 
the invoice is received by the buyer .

Performa Invoice is a only a part payment of received 
agaist purchase order for advance  agaist L.C. created 
receiveble amount as per P.O.
ther is not counted  in Tax's only on advances.

proforma invoice is an invoive or quotation sent by exporter to buyer before commercial invoice in which a particular estimate of product demanded is sent & is not recorded as 'accounts receivable' by exporter or 'accounts payable' by buyer.it's not a true one.
     invoice is the one sent by exporter to buyer in which a detailed description of goods with quantity,price,weight etc. is provided with an accurate amount to be paid & is recorded as 'accounts receivable' or vice versa. it's the true one.