The Green Card is officially known as Form I -551. It is named as Green Card because of the color it had long before. This card is officially issued by the government of US to immigrants as evidence of permission to lawfully stay in the US. This card gives its holder permanent right to work and stay in the US. This card has to be renewed from time to time and there is a strict procedure to do that.
'''How to get the form'''
You have to apply for renewal of Green Card within six months of its expiry. You can get Form I-90 through mail or by requesting over phone. In certain places like Chicago, New York, Houston or San Francisco etc, you can apply via mail. But in other places you have to submit your application physically in USCIS district office or its Sub Office.
When you visit the USCIS office for submitting your application, carry your passport along with you or else a photograph so that a provisional document can be issued to you on temporary basis.
If your passport has already expired then also the USCIS will give its stamp on it but this will not suffice for verification of employment. In that case you can either submit a stamped passport which has not expired or Form I-94 with your photograph. You should refer to Form I-9 for the documents that you can submit. Make sure that you update the USCIS that you require provisional documents for employment purpose.
It takes almost 10 to 12 months to get fresh Green Card. The temporary evidence of your status is applicable for 1 year.