Some DNS definitions you might need by Scott Taggart

Type: The type will usually give you a choice between A, AAAA, CNAME, MX and NS. If you want your host to point to a normal IPv4 (standard) address choose the A record, equally if you want an IPv6 (non-standard currently) address, choose AAAA. If you want your hostname to point to another hostname, use a CNAME record. For more advanced users with separate mail servers, an MX record can be used to point to another domain to tell mail servers where to deliver for that domain. Finally, for private domains only, you can add an NS type record, this can redirect resolution for that particular host to another nameserver... if you are only using ODS for DNS, you will not need to add any NS records for your domains

IP/CNAME: This bit is easy enough, you simply enter the IP you want the hostname to point at (for A/AAAA records (or NS records for private domains)) or you can enter a hostname if you have chosen to create a CNAME or MX record

TTL/Priority: This is a setting that normal users do not need to worry about, if you do not know what this is, leave it blank. This setting will apply to MX and A records only. The default TTL for A records is 180 and the default priority for MX records is 10. You can adjust these values for any hostname if you want