A multi-core processor is a computer processor integrated circuit with two or more separate processing units, called cores, each of which reads and executes program instructions, as if the computer had several processors. As the name suggests, the Octa-core processor is made up of eight processor cores that power Galaxy smartphones. The cores in octa-core chips are basically two quad-core processor sets, the cores in one of the sets are relatively less powerful when compared. Hi in this video I have tell what is singal core, Dual core, Quad core and octa core difference. The terms octa-core and quad-core denote the number of processor cores in a CPU. These Octa Core processor mobile phones offer the right balance between performance and build quality.