If after these trades price is higher you will here “up” sound, one bitcoin to usd lower, “down” sound, and if it stays the same “no change” sound. If you set it to 0.
This setting is currency specific setting. It won’t work if you switch to another currency. The chart below is the price change over time. The yellow line is the price at which actual trades were made. Green and red areas near the yellow line show you maximum and minimum price. Price is shown on the right axis. The Value for this is shown on the left axis.
Below is the cumulative depth chart. Moving your mouse over it will give you more information. The value axis for the cumulative depth chart is on the left, enumerated in . They show market depth changes over the last 10 minutes. The value axis for them is on the right . Bars on the left of the current price are bid offer changes, and on the right ask offer changes. So if somebody is adding a bid offer, you will see a green bar up on the left.
About colors: if bids are added they are in green, and when removed they are in red. The big number here is the price at which last trade was made. And here we have the last trades table. On the left: amount of bitcoins traded.