Karate-do evolved in the islands of Okinawa under Japanese Sovereignty, and was influenced by the Chinese styles of “Kung Fu” from the Shaolin Monasteries. Hence four main styles evolved and are still practiced today and are Shoto Kan; Shito Ryu; Wado Ryu & Goju Ryu. However, today there are many sub divisions within each style and in fact in Mumbai alone there are 9 different styles of GOJU RYU alone, all officially represented to their parent Organizations in Japan.
The main difference is not in the styles but rather if the Karate-do Institute is teaching Sports Karate or Traditional Karate-do. If it is the former then all students are taught sports Karate which dilutes the true meaning of Karate-do, and would probably mean the end of their training after 30 years of age. If it is the latter then in all probability this Karate-do Institute would concentrate on a high level of Fitness and Un-armed combat, and enable the student to train even in his Eighties like our teachers in Okinawa.