Classical measurements, introduction, theory of errors, systematic and random errors, Gaussian distribution, weight of measurements, error and weight propagation, conditional direct measurements, complex errors, classical electrical measurements, organology of basic measurements, methodology of basic measurements, acceptance instruments, zeroing instruments, measurement of energy and power, measurement of power in polyphase systems, electronic and digital measurements, introduction, amplifiers, open-loop amplifiers, closed-loop amplifiers, analog measurements, operational amplifiers, measurements on operational amplifiers, measurements of electrical quantities, measurements of non-electrical quantities, digital measurements, digital systems, measurements of electrical quantities, measurements of non-electrical quantities, analysis of error in digital filters, rounding noise, exercises, introduction, laboratory exercises, exercises in error theory, exercises in classical measurements, exercises in electronic measurements, bibliography.