You can order your messages, media and files to self-destruct in a set amount of time after they have been read or opened by the recipient.
And when you delete messages on your side of the conversation, the app on the other side of the secret chat will be ordered to delete them as well. On top of this, Messages cannot be forwarded from secret chats. This means only you and the recipient can read those messages. All messages in secret chats use end-to-end encryption. “Secret chats are meant for people who want more secrecy than the average fella.
If you are not practical with the concept of Telegram’s Secret Chat: For whom is following me on Twitter this is not a news, yesterday I was complaining about a Telegram “Feature” in the secret chat context, while for whom doesn’t this should serve as a write-up of the bug that I have discovered (The bug is nothing fancy but something I think people should, at least, know).