Linux中的文件权限与Windows中的权限

In linux, if I have a file I'm sharing with a group, and I put the file on a USB memory stick, for example, and copy it to a computer that doesn't have the same group or users, does the file have no permissions for anyone on that new computer? What if I bring a linux file that only lets user X to read it to a windows machine? Who gets to read it on the windows machine? since user X (and group) doesn't exist on that machine. In linux, if I have a file I'm sharing with a g