What is the format for formal letter and informal letter

There is a manner prescribed for writing formal letters. As opposed to informal communication, which does not follow any format. Formal letters are usually written in the third person, however, for business letters, first person is used. On the contrary, informal letters are written in first, second and third person.

the central idea of the above passage is following;

central idea: cultural study is very important specially archaeology. grimm's stories very well cater to the importance of cultural relevance.

explanation:

i’m alive so yes and the author is a technique idiom