Kosovo is technically a country (at least, I see it as one), but it is not in the official published list of UN recognized countries. Hopefully it will be soon though! Palestine is on the list, however, despite some debate. Gaza strip isn't recognized as its territory though. Both are countries, it just comes down to what's on the official list. Similar to the situation with North/South Korea, where some countries don't recognize North Korea but it is still part of the list and recognized by the UN, despite the debate.
Palestine is not a recognized country, but Kosovo is.