This lecture covers the sources of noise interference in electronic systems, including external factors like thermal, magnetic, and electromagnetic fields, as well as internal factors such as ground loops and common resistance paths. It delves into the classification of interference based on signal type, location, and quantity, highlighting the sensitivity of components like samples, input cables, and preamps. Specific types of interference, such as thermal EMF, chemical EMF, triboelectric effects, magnetic EMF, capacitive coupling, and inductive coupling, are explained in detail. The lecture also explores how interference can manifest as unwanted DC and AC voltages/currents, affecting the performance of electronic circuits and amplifiers.