AutoCAD provides the ability to assign how things plot/print such as lineweight, color, dithering etc. using a feature named Plot Styles. You have the choice to use the default color-dependent or named plot styles, but your drawing can only be one or the other.
- Color-dependent plot styles (CTB)
- Named plot styles (STB)
It can be debated as to which is better but I will leave that for you to decide which works best for you and the people you exchange DWG files with. About 95% use CTB most likely because that is not only the default but the way they have always done it. If you want to share your reasons for using one plot style method over the other please feel free to post a comment to this blog post.
AutoCAD comes with drawing templates for both CTB and STB drawings. If you need to convert an existing drawing from one to the other you can use the following commands at the AutoCAD commandline.
To Convert Drawing Plot Style Modes:
To convert a CTB mode drawing to STB mode or a STB mode drawing to CTB mode use the command CONVERTPSTYLES.
To Convert Drawing Plot Style File such as Shaan.ctb to Shaan.stb:
To Convert a CTB Plot Style file use CONVERTCTB.
Dont let the name fool you, CONVERTCTB will work to convert a CTB to STB to a STB to CTB.
More on the two plot styles:
The majority of AutoCAD users are using the default plot style of color based plot styles also known as color-dependent plot styles (CTB). CTB plot styles has been the default since the early days of AutoCAD supporting plotting/printing. It comes from the days when we had pen plotters and there was 255 numbered pens available which correlated to the physical pens. With a CTB plot style table you can specify the color, lineweight, linetype, screening, and so on that objects of a specific color will have when plotted.
With AutoCAD 2000 came the style based plot styles or named plot styles (STB) option was added allowing you to assign plot styles including color, lineweights, screening to an object regardless of colors or layer set to the object. Some users mention the benefits of STB are less pen styles to manage or they can have project phased styles.
AutoCAD Online Help on Plot Styles Use a Page Setup to Specify Plot Settings
Some visual flashback on the evolution of color in AutoCAD
Here is the early AutoCAD ACI colors.