Could you please elaborate on what constitutes a capital gain when selling a cryptocurrency? Specifically, I'm interested in understanding how the calculation is made and what factors are taken into account. Does it involve the initial investment amount, the selling price, or both? Are there any taxes associated with capital gains on cryptocurrencies, and if so, how do they differ from traditional investments? Clarifying these points would help me gain a better understanding of the financial implications of trading cryptocurrencies.