You can choose between different types of vote duplication checking.
IP-Address
Most secure method to ensure vote accuracy, but does not work if your voters share the same network/wifi (e.g. in schools, universities or workplaces).
Browser Session
This method allows one vote per browser session. Choose this setting only if you are confident that your voters will not manipulate.
None
This setting allows participants to vote multiple times. It is only recommended for testing or when participants also enter their name while voting.