Color in short

color c1 = color(255,0,0); // r = 255 g = 0 b = 0 values
color c2 = color(127); // r = b = g = 127 -> grey
color c3 = color(127,60); // r = b = g = 127 -> grey, with alpha channel of 60
color c4 = color(0,255,0,100); // r = 0 g = 255 b = 0 and alpha channel of 100
// the alpha channel ranges from 0 to 255. 0 is transparent, 255 opaque