What is meant by magnetic induction ?

Explanation

The magnetic induction (total magnetic field) inside the specimen `vecB` is equal to the sum of the magnetic field `vecB_(0)` produced in vacuum due to the magnetising field and the magnetic field `vecB_(m)` due to the induced magnetisation of the substance.
`vecB = vecB_(0) + vecB_(m) = mu_(0)vecH + mu_(0)vecI = mu_(0)(vecH + vecI) = mu_(0)(vecH + vecI)`