Hello Aman,
BBA:
As the name indicates, BBA (Bachelor in Business Administration) is a course in business administration that is a level lower than MBA that is a graduate level degree course in management. BBA is a three year professional course that is divided into 6 semesters that include various subjects such as HRM, accounting, finance, marketing, entrepreneurship, MIS, operations management etc. It is thus a good course designed to give an insight into the field of management while making a student industry ready as many who do not wish to study further get absorbed in many industries such as banking, financial institutions, and corporations. 

BCA:
BCA is a technical degree and the student can hope to learn the concepts of hardware, software, computer languages, programming etc. After completion of BCA, it is prudent to enroll in MCA which is technical degree equivalent to BE and opens the doors for lucrative job options in all industries.

Difference:

• BBA is a management course while BCA is a technical course in the field of computers
• The concepts of BCA are easier for students having done their 10+2 in science subjects while for others, BBA is better.
• Both BBA and BCAare launch pads for graduate level degrees and open the doors for great careers in many industries.