Samba public folder without password

mkdir /home/public
chmod -R 777 /home/public

Create the public folder with no restrict permission 1st. In /etc/samba/smb.conf

If the section [global] of smb.conf is under security = share,
You just only modify:

[public]
    comment = Public 
    path = /home/public
    public = yes
    guest ok = yes
    writable = yes
    printable = no

If the section [global] of smb.conf is under security = user,
You need to modify:

[global]
    .
    .
    .
    map to guest = bad user
    guest account = nobody


[public]
    comment = Public 
    path = /home/public
    public = yes
    guest ok = yes
    guest only = yes
    writable = yes
    printable = no

Restart the samba service, then you connect to \\server\public without any password