This is common if you have a small subnet delegated from your ISP. It's called RFC 2317 delegation or something like that.
Many ISPs will have you create a PTR record, under your domain (i.e. oscar.com which you have control over), and put a CNAME in their reverse zone (i.e. 0.168.192.in-addr.arpa which the ISP has control over).
For example, for an IP address of 221.222.223.15, the reverse record would be 15.223.222.221.in-addr.arpa. A reverse lookup would look for that record from the owner of the IP address (in your case, myhosting.com or their parent ISP).
The ISP would normally have a record like
15.223.222.221.in-addr.arpa IN PTR net223ip15.myhosting.com
But in the cname delegation method, they have something like this:
15.223.222.221.in-addr.arpa IN CNAME 15.oscar.223.222.221.oscar.com
Then you create a record in your zone like this:
15.oscar.223.222.221.oscar.com IN PTR www.oscar.com
Then folks will look up 221.222.223.15 and follow the CNAME from 15.223.222.221.in-addr.arpa to 15.oscar.223.222.221.oscar.com to www.oscar.com.
I've never had this done for a single IP, but I've had several ISPs do something like this for routed subnets.
Check with myhosting.com to see if they have a preference or specification for the record. But I think this is the general story behind the delegation.
Matching the PTR and A records makes it possible to verify the claim made in the PTR record by automated means.
If the A record isn't provided, one must go to the whois records to verify whether the PTR record accurately represents the entity in control of the IP address, a tedious manual process that's difficult to automate and is often wrong or out of date.
This is important for security reasons in many contexts. One that I'm familiar with and will give you an example for is:
Let's say you run a web site and post unique content, but you have discovered your content is being copied to other web sites, and worse, they're ranking higher than you in the search engines!
After hours of staring at your logs wondering how in the world somebody slipped a bot past your defenses, you finally notice hundreds of requests from Googlebot. But when you eventually look up one of the IP addresses, you find it registered to Bulletproof Ukraine Web Hosting and not Google. You thought you were getting indexed but instead you got played.
How do you solve this problem? Easy, you compare the PTR record to the A record. Google even recommends this approach.
This can be automated in many Web programming languages (PHP is a notable exception; you cannot do this reliably in PHP) so that a Web app can check the IP address, see that the PTR is *.google.com and then uses the A record to confirm that *.google.com matches the same IP address. If there's a mismatch somewhere, you have discovered a fake Googlebot.
Best Answer
To add a PTR record in the GoDaddy DNS Manager, you need to do the following:
A window will open with 4 tabs (Inbound, Outbound, The well hidden 'PTR' and Outsourced)