Friendly letters, or personal letters, must consist of five parts: the heading, the greeting, the body, the complimentary close and the signature line, according to English Plus. Sometimes they also contain a postscript.
The heading, indented to the middle of the page, includes the sender's address, line by line, as well as the date. A blank line follows it. The greeting may be formal or informal, depending on the circumstances, and uses the recipient's given name or relationship.
Indented paragraphs typically craft the body of the letter, says English Plus. The complimentary close consists of a few words on a single line and ends in a comma. The signature line has the sender's printed name on one line with a handwritten signature on the following line.