This is the 1871st most frequent Russian word.
письмо
Letter; written message.
Here, 'письмо' (letter) refers to a written message sent by someone.
Я получил письмо от друга.
I received a letter from a friend.
'письмо' (letter) refers to an email message in a digital format.
Мое письмо отправлено через электронную почту.
My letter was sent via email.
'письмо' (letter) pertains to traditional handwritten communication.