# Graphical Components and Mapping Strategies

This section discusses:

* **Graphical components** i.e. individual components of graphs
* **Mapping strategies** i.e. mapping between data and graphics

It is important to know about graphical components and mapping strategies because it helps to:

* **evaluate visualizations**: with an in-depth understanding of the above, we will be able to criticise design choices
* **re-design evaluations**

**Visual Encoding** refers to the strategies/rules used to turn data into graphical representations. More precisely, it refers to the mapping between:

* data items $$\leftarrow\rightarrow$$ visual marks
* data attributes $$\leftarrow\rightarrow$$ visual channels
