In simple terms, a passport is an internationally recognized travel document that verifies the identity and nationality of the bearer. A unexpired US passport is needed to enter and leave most foreign countries. It is the US Department of State that is the sole authority that issues or verifies US passports.
The US passport comes with different validity periods.
If you were 16 years old or older when the US passport was issued, it is valid for ten years.
If you were 15 years old or younger when the US passport was issued, it is valid only for five years.
You can apply for a US passport at more than 9,000 locations available nationwide. These facilities include many Federal, state, and probate courts, post offices, some public libraries, county and municipal offices.
For expedited requests, you have thirteen additional regional passport agencies and one Gateway City Agency designated to serve if your intended travel is within fourteen days, or if you need a foreign visa for travel. Under such circumstances, prior appointments are required.
If you are applying for the first time, you have to apply for your US passport in person.
Some other instances also require you apply in person. They include :
your passport expired and is not in your possession
your passport expired and was issued more than fifteen years ago
your previous passport was issued when you were under the age of sixteen
you have a current US passport and that is lost or stolen.
Apart from the circumstances mentioned above, you should appear in person if you are under the age of fourteen, and you should be able to provide legal consent of your parents or legal guardians. In such cases, you should either be accompanied by both the guardians, one guardian who can provide the other guardian’s notarized statement of consent, or one guardian who can submit evidence of soul authority to apply.
Applying for Passport In Person:
You are required to file Form DS-11 if
you never had a US passport before
you are under sixteen years of age
your current passport was issued more than fifteen years ago
your current passport was lost or stolen.
You have to file Form DS-82, Application for Passport By Mail to renew a previously issued US passport by mail at anytime OR in person at a Regional Passport Agency if you are traveling overseas or need your passport for foreign visas within fourteen days.