When we load vector layers, QGIS renders them using a default style and a random color. Of course, we want to customize these styles to better reflect our data. In the following exercises, we will style point, line, and polygon layers, and you will also get accustomed to the most common vector styling options.
Regardless of the layer's geometry type, we always find a drop-down list with the available style options in the top-left corner of the Style dialog. The following style options are available for vector layers:
Single Symbol: This is the simplest option. When we use a Single Symbol style, all points are displayed with the same symbol.
Categorized: This is the style of choice if a layer contains points of different categories, for example, a layer that contains locations of different animal sightings.
Graduated: This style is great if we want to visualize numerical values, for example, temperature measurements.
Rule-based: This is the most advanced option. Rule...