# Messages

> Write to your teacher and share files.

**Messages** is your conversation with your teacher. On a school site, choose the teacher first. The Messages tab shows how many messages are unread.

- Ask a question, share a file or plan the next lesson. A message can be up to 4000 characters.
- Press Ctrl or Cmd and Enter to send.
- **Attach a file**: a PDF, PNG, JPEG or WebP of up to 10 MB. If the site has no file storage, attachments are off.
- **Delete message** removes one of your messages and its file.
- **Seen** under your latest message means your teacher has read the conversation up to it.
- If your teacher does not read a message within a few minutes, they get an email. You get one too when they write and you have not read it.
- To keep conversations calm, you can send up to 8 messages a minute and 60 an hour.

If your teacher closes the conversation, you can still read past messages and see your lessons, but cannot write. See [Reporting and blocking](/docs/students/reporting-and-blocking).