Me and my colleague had applied for a temporary resident visa to Canada and stated the purpose of visit as Business. But my colleague has received "B-1 Visitor Business" whereas I have received only "V-1 Visitor". What is the difference? Will I require a "B-1 Business Visitor" as well?

Both are essentially visitor visas, but are classified differently. Without knowing how the two applications were presented, it is hard to know if this is an error or due to differences in the cases. Assuming that the purpose of your visit was stated accurately in the application, further documentation or correction should not be needed.