If a site is having more than one domain, then google decreases the ranking or not..? Example: There are two websites : xyz.com and xyz.uk , so is there will be decrease in ranking of xyz.com because of xyz.uk or not ? Thanks in Advance !
Personally if you own both, I would 301 redirect one to the other. If you;re in the UK, have the .com point to the .co.uk and if you're outside the UK have the .co.uk point to the .com... I think trying to rank for both will lead to some unwanted stipulations.
No, there are different domain unless both of the domain have same content. if you own both, then better redirect them