TYPES OF LETTER:
1) FORMAL LETTER
2) INFORMAL LETTER
1) FORMAL LETTER: A Letter written for a formal purpose is called a Formal letter. It addresses a serious issue. These are sometimes known as business letters. Examples: Letter to the editor, Letter to the Government, Letter to the police, Letter to the principal, Order letter, Complaint letter, Inquiry letter, Business letter, Application letter.
2) INFORMAL LETTER: A Letter written for an informal purpose is called an Informal letter. It is written for a casual purpose. These are letters to friends and relatives, or people you know well.Examples: Letter to parents, Letter to siblings, Letter to friends, Letter to classmates, Letter to neighbours.
Basis for comparison
A formal letter is a letter, written in formal language, in the stipulated format, for official purpose.
A letter written in a friendly manner, to someone you are familiar with, is called informal letter.
Business, college/institute, employer, organizations, etc.
Friends, family, acquaintances etc.
Long and complex
Short and simple