what is the difference between a float[] and a float[,]?

This is probably a simple javascript question. I want to use the GetHeights function to use for generating terrain hights. i noticed this function returns a float[,] and am not sure what the comma in there means. Thank you for your help.

This means that the array returned has two dimensions - it’s like a matrix, with columns and rows.

This function returns a rectangular portion of the entire height map:

function GetHeights (xBase : int, yBase : int, width : int, height : int) : float[,];

where xBase and yBase show the starting column/row, and width and height tell how much columns and rows will be returned.