Pattern libraries versus style guides
What's the difference between pattern libraries and styles guides and when should you use each? The answer depends on what stage of design you are in. For example, if you are wireframing (see Chapter 7, Tools, for more on wireframing), you will want to use patterns. Patterns are proactive design elements that help define and visualize interactions and information architecture.
Once you have completed the design phase, you are ready to create the style guide, a documentation of all your design decisions. The style guide will be used by the visual design and development teams to ensure that what they deliver is consistent with what you envisioned.
Both the pattern library and the style guide are living documents. As design changes occur, both should be updated accordingly.
Note
For additional resources on pattern libraries and style guides, see Chapter 8, Final Thoughts and Additional Resources.