Explore the fundamental concepts of sampling and reconstruction in signal processing through this 20-minute introductory lecture. Delve into the Nyquist sampling rate and understand the effects of aliasing. Gain insights into Fourier Transform, Sampling Theorem, and Ideal Lowpass Filter. Examine graphical representations and First Order Hold techniques. Connect these concepts to real-world applications in digital communications and signal analysis. Enhance your understanding with related videos covering topics such as negative frequency, aliasing ambiguity, and complex numbers in signal processing.