I am struggling to understand what the following / after an IP address (not .0 or .255) is telling me. This is from MS's website: Outlook.com Outbound IP Space Outlook.com sends e-mail from the following IP addresses: * 65.54.190.0/26 * 65.54.190.64/26 * 65.54.190.128/26 * 65.54.190.192/26 Is the /...