Internal trade refers to the trade within the geographical boundaries of a country. Payments in this kind of trade are made and received in the same country. Thus, this trade is internal and hence it is also termed as Home or Domestic Trade.
Wholesale trade refers to the trade in which the trader buys in large quantities from the producer or manufacturer and sells them to other merchants in small quantities. The person engaged in this trade is termed as “wholesaler”. He acts as a middle man between the producer/ manufacture and the retailer.
Retail trade is concerned with buying of goods in small quantities from the wholesaler and selling them in small quantities to the ultimate consumer as per their requirements. The person engaged in this trade is called the ‘retailer’. He acts as a link between the wholesaler and the ultimate consumer.