kindly explain it thorougly, this is for my presentation tomorrow,

According to the method of transmission, we have the circular and the specially advised.

a. Circular. A letter of credit is termed circular when the opening bank issues a letter addressed generally to person or companies indicating its intention to honor the drafts of the beneficiary under the terms specified therein.

b. Specially advised. On the other hand, when the opening bank directly notifies the beneficiary or through a notifying bank (usually a correspondent bank), the letter of credit is known as "specially advised."