A letter is a written message on a paper that is carried from one person or group to another. The United States postal service handles more than 484 million mail items each day which equals 20.2 million pieces per hour. Letters are an important part of history for thousands of years.
It is assumed by the ancient historian Hellanicus that the first handwritten letter has been sent in 500 BC by Queen Atossa of Persia. But over time the popularity of letters grew as people became more literate. In today letters can be sent over a popular electronic medium like emails, instant messaging etc.

So How Much Does A Standard Letter Weigh?
The letter that comes inside an envelope weighs around 0.159 ounces or 4.5 grams. On average the envelope paper weigh approximately 0.238 ounces or 6.75 grams. SO, the standard letter weight is around 0.397 ounces or 11.25 grams.
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In recent years electronic forms of communication have taken over handwritten letters but people still use handwritten letters. In accordance with Pen Heaven, this ratio is 64%.
Fun Facts:
>>In 1792 George Washington signed the Postal Service Act that makes it illegal to open a letter written for someone else!
>>In the 17th and 18th centuries letters were used for the self-educating purpose.
>>Alexander Pope is the first English writer who published his own letter.
>>To receive a letter you don’t need any device or anything else. You just need a proper postal address.