What does this syntax [0:1:5] mean (do)? : I thought it was a matrix, but it doesn't seem to match the syntax for a matrix.

Here is the entire context:

    function [x , y] = plotTrajectory(Vo,O,t,g)
    % calculating x and y values
    x = Vo * cos(O) * t ;
    y = Vo*(sin(O)*t)-(0.5*g*(t.^2));
    plot (x,y);
    hold on
    end
    
    for i = (0: (pi/8): pi);
    [x,y] = plotTrajectory(10,i,[0:1:5],9.8);
    end