with the S4 you can use samsung kies or you can copy them to your sim card as this will only save name and phone number. you can see if AT&T address book is compatible with your phone and you can export a file of your contacts if you have an sd card in the phone.
Your best option is to export them to storage and then use a usb cable to transfer the file to the PC. Within the settings of your people/contacts app, you should have the option to export to storage/sd card. This will save the them as a cvs file on the root of the storage drive/sd card. Once connnected to a PC, navigate to the file location and copy to the PC. With this cvs file, you can transfer to another device to add the contacts to that device or with a program on PC that will open the cvs format, you can view or import your contacts on the PC.