Hello, 

Master of Science is a post graduate degree that can be pursued after the graduation in related subjects. The B.Sc. degree usually covers the science subjects including social sciences. The candidates who wish to study these subjects on a wider level can opt for M.Sc. in related subjects.
Integrated Msc is that you can complete postgraduation along with bachelors in 5 years instead of 6 years.

Hope this helps...