There are two semesters in a year: Spring and Fall semester

There are two IAP sessions in each semester of the Intensive Arabic Program (IAP) - session 1 and 2. 
Each session is 2.5 months long. Students can start the program from any session of a semester. 

No matter what session/semester is running currently, a student's first session will be the one they start with by enrolling into.
If a student missed the enrollment of session 1, he can enroll in session 2 of that semester and start the program. For him, session 2 will be his first session. This means that he will enroll in the first course of this program, i.e. IAP Arabic 101.  

There are two semesters in a year: Spring and Fall semester

There are two IAP sessions in each semester of the Intensive Arabic Program (IAP) – session 1 and 2. 
Each session is 2.5 months long. Students can start the program from any session of a semester. 

No matter what session/semester is running currently, a student’s first session will be the one they start with by enrolling into.
If a student missed the enrollment of session 1, he can enroll in session 2 of that semester and start the program. For him, session 2 will be his first session. This means that he will enroll in the first course of this program, i.e. IAP Arabic 101.