Student pilot certificate

In the United States, a student pilot certificate is issued to a pilot in training, and is a pre-requisite for the student to fly alone in the aircraft, or "solo". It is no longer initially issued by a medical doctor who is also an authorized aviation medical examiner (AME), in conjunction with the student's first medical certificate. Instead, as of April 1, 2016, the AME gives the student a medical certificate. With that being said, a medical certificate is required. The classification of the medical does not matter at this time, but it is suggested that the student get a first-class medical to know if he or she can pass the more difficult tests. The student takes the certificate to his or her instructor who then completes an application. All applications are completed on the Integrated Airman Certification and Rating Application (IACRA). This is a Federal Aviation Administration portal that allows for documents and applications to not have to be mailed. The student pilot should fill out the form and have his or her instructor check all forms before submission. The easiest way for this to be accomplished is to sit and fill out the forms with the instructor, as there is a lot of back and forth in the process. The student must fill it out, then the instructor does a portion, and the cycle repeats. The application is sent to the FAA which will send the student pilot certificate to the student. A temporary certificate should be available after the form has been approved, which takes approximately two weeks. This temporary paper can be used during the actual solo flight until the physical card arrives in the mail. Although this student pilot certificate does not always come right before a solo flight, it is required, and thus earning a student pilot certificate is a sign that a solo flight may be near.
Obtaining a student pilot certificate authorizing solo flight requires four steps:
Although there are minimum ages for licenses, there is no minimum age for when flight training can occur. In the aviation industry, time is money, and all time should be logged. So if a prospective student goes flying at 12 years old, and the pilot is showing them the airplane and how it flies, the prospective student should log the time. Although it may seem unneeded at this time, it will pay off later. 
Private pilot licenses require a minimum of 40 hours. Commercial licenses require a minimum of 250 hours. In order to be considered for an airline position, most airlines require at least 1500 hours of total flight time.
Student pilot certificates allow students to fly the plane by themselves, with instructor sign-off. This is a big step in the aviation journey and should not be taken lightly. The time logged flying under the student pilot certificate is PIC (or pilot in command time). This means that all responsibilities are on the student pilot.
There are limitations to this student pilot certificate. Students still can only fly under VFR, or visual flight rules. Additionally, they are still under the instruction of their instructor. This means students are unable to rent a plane and fly wherever they choose for the day. Lastly, they may not fly for compensation or hire as a student pilot.