The discussion focuses on the functions of memory buttons on basic calculators, specifically M+, M-, and MRC. M+ adds the current number displayed to memory, while M- subtracts it. MRC is used to recall the stored number. An example illustrates how to use these functions: after clearing memory with MRC and M-, pressing 5 and then M+ stores 5, followed by pressing 4 and M+ to store 4, resulting in a total of 9 when recalled. Subtracting 3 using M- updates the memory to 6. The conversation highlights the utility of these functions for performing basic arithmetic operations efficiently.