How do computers handle ascii / text & images / color differently?

Recently, I have been thinking more about what computer hardware is to work to produce what we expect.

Comparing text and color, it seems that both rely on combinations of 1 and 0 with 256 possible combinations for each byte. ASCII may represent a letter, such as (01100001), with the letter "A". But then there may be a color R (01100001), G (01100001), B (01100001), representing some random color. Given the low level, the computer just reads these collections 1 and 0, what should happen for the computer to display the color R (01100001), G (01100001), B (01100001), and not the letter A three times on my screen?