Legally...
போஸ்ட் செய்யப்பட்டது Houssem Khaled அதில் ஸ்பெயின்அமைப்பு
When I went to do my NIE, they told me the NIE was valid for 3 months (even if you renew it, it will still be valid for another 3 months, etc.) while the resident card allows you to stay longer in Spain without having to go through the trouble of renewing it as often as the NIE. Can someone confirm that?