What is the "%" character in stdout?

Question

linux

Sometimes the character "%" appears in stdout.
For example, there is such a python script

#!/usr/bin/python
import socket
sock = socket.socket()
sock.bind(("127.0.0.1", 8081))
sock.listen(5)
conn, addr = sock.accept()
conn.send(b"Hi!")
conn.close()

I connect with netcat to the server, I get in stdout

~/python/http> nc 127.0.0.1 8081
Hi!%

What does the "%" symbol mean?

Answer 1

This shell says that there was no \n (line break) at the end, so "I put it myself so as not to break the appearance of the console"