what is the mean of RGBA

Answer 1

red-green-blue-alpha.

Any color can be represented as a combination of red, green, and blue. Yellow for example is just all red and green and no blue (`rgb(255,255,0)`). Google "color picker" to get the rgb values for any color!

Alpha means 'transparency'. If you put a yellow square with alpha 0.5 (`rgba(255,255,0,0.5)`) on top of an image, you will see the image shine through.

r, g, and b go from 0 to 255, a goes from 0 to 1.

Answer 2

RGBA Colors. RGBA color values are an extension of RGB color values with an alpha channel - which specifies the opacity for a color. An RGBA color value is specified with: rgba(red, green, blue, alpha). The alpha parameter is a number between 0.0 (fully transparent) and 1.0 (fully opaque).