i want to know how to copy movies from my hard drive wd to my mac
What's your file system of the hard drive, if the partition on your hard drive was formated as NTFS, it could not be read by MAC OS unless use some third-party software which could make NTFS be readed in MAC ( I don't know it is free or not).
If you do not want to use third-party software, you could reformated your hard drive to FAT32 file system which could be readed both in Windows OS and MAC OS. But you should notice that fat32 file system could only support the single data which is smaller than 4GB.
Hope this could help you, best regards.