The names of the three tables in Video RAM for characters are :

NAME : The screen (24x32)
PATTERN : The characters pattern (256 characters : HEX values 00-FF)
COLOR : The characters color(s)

A character have the same pattern and color anywhere on screen (one exception in screen mode 2). So you can't use the same character to print a blue 'A' and a red 'A' side-by-side. The solution is using two characters with the same pattern but with different colors.

In the ASCII code, the character '1' is the character 49 (31 in HEX value). You must understand the difference between the ASCII code and the symbol. The ASCII code for the character 'A' is 65 (41 in hex value).

Now, if the color of the character 'A' is blue and if you change the pattern of the character '1' to looks like an 'A' but with a red color, then you just have to print the characters 'A' and '1' side-by-side on screen to show two 'A' side-by-side... one blue and one red.

In the NAME table, there is HEX values 41 for the 'A' and 31 for the '1'.
In the PATTERN table, there are identical HEX values for the character 'A' and '1'.
In the COLOR table, there are diffirent HEX values to have blue color(s) for the character 65 ('A') and red color(s) for the character 49 ('1').

If you understand, you have enough knowledge to start programming your first ColecoVision game by using only characters (tiles). DACMAN is a good example of a video game based on characters graphics.