The importance of measuring instruments is well known in the various engineering fields. The book provides comprehensive coverage of various electrical, electronic and digital instruments, instrument transformers, measurement of power and energy, d.c. and a.c. bridges and oscilloscopes. The book starts with explaining the classification and requirements of a measuring instrument. Then the book explains the PMMC, moving iron and electrodynamometer type instruments. Extension of range of instruments using shunts and multipliers is also included in the book. The book includes detailed discussion of instrument transformers and power factor meters. The book covers the types of wattmeters, errors and compensations. The chapter on energy measurement includes discussion of single and three phase energy meters, errors and compensations. The book teaches the details of d.c and a.c. potentiometers along with their applications. The book further explains various d.c. and a.c. bridges along with necessary derivations and phasor diagrams. It also includes the discussion of various magnetic measurements. The book incorporates the discussion of oscilloscopes. It also explains the various oscilloscope measurements and Lissajous figures. Finally, the book includes the discussion of various digital meters such as digital voltmeters, digital multimeter, digital frequency meter and digital tachometer along with the automation in digital instruments. Each chapter starts gives the conceptual knowledge about the topic dividing it in various sections and subsections. Each chapter provides the detailed explanation of the topic, practical examples and variety of solved problems. The book explains the philosophy of the subject which makes the understanding of the concepts very clear and makes the subject more interesting.