Question

Define the terms Input offset voltage and Input bias current of opamp.

Answer 1

The input offset voltage is a parameter defining the differential DC voltage required between the inputs of an amplifier, especially an operational amplifier, to make the output zero. An ideal op-amp amplifies the differential input; if this input is 0 volts, the output should be zero

An ideal op-amp has no current flow at the inputs. The world is not ideal. In the real world, tiny amounts of current actually do flow into both the non-inverting and inverting inputs of your component. These currents are referred to as the input bias currents, IB+ and IB