This lecture covers the process of quantizing and coding digital signals, starting with the conversion of analog to digital signals through sampling, quantization, and coding in bits. The instructor explains the concept of uniform quantization, where the amplitude intervals are divided equally, and the quantization step is determined. The lecture also delves into the calculation of the number of bits required for representation, the error introduced during quantization, and the signal-to-quantization noise ratio. By analyzing the power of the signal and noise, the instructor demonstrates how the signal-to-quantization noise ratio evolves linearly with the number of bits used for quantization, providing insights into optimizing the trade-off between signal representation and noise levels.