How do you calculate daily volume?

Excuse me, could you please elaborate on how exactly one calculates daily volume in the cryptocurrency market? Is it a straightforward process that involves simply adding up all transactions within a 24-hour period, or does it involve more complex metrics and considerations? Are there any specific exchanges or platforms that are considered more reliable sources for accurate daily volume data? Additionally, how does one account for wash trading or other potential forms of manipulation when calculating daily volume? I'm eager to gain a deeper understanding of this process.