Describing a chart especially a pie chart is a straightforward writing. Why? Because you only need to identify the parts or the sections that have differences or similarities like the biggest, the smallest, those with equal size, or the ones which are almost the same size.

Consider this circle graph or pie chart below.

Flickr photo by:
jimmiehomeschoolmom

What are the similarities and the differences you can see in the chart?

-The cars (43%) have the biggest number followed by taxis (17%).

-The bicycles and the wheelbarrow are the smallest (1% each)

-The buses (13%) and the motorcycles (13%) have the SAME number; likewise the bicycles (1%) and the wheelbarrow (1%).

-The number of bicycles (1%) and the wheelbarrow (1%) are just HALF of the number of the three wheels (2%).

-The trucks (8) are ALMOST half of the taxis (17).

-The COMBINED number of buses (13%), motorcycles (13%) and taxis (17%)have the SAME number as the cars (43%).

The COMBINED number of bicycles (1%) and the wheelbarrow (1) are EQUAL with the number of three wheels (2%).

-The COMBINED number of buses (13%)and motorcycles (13%)are ALMOST THE SAME as the number of taxis (17%) and trucks (8%)COMBINED.
It is easier to interpret a chart if we start with the most obvious sections like the biggest, the smallest, and the equal size. Then proceed with the other combinations and find out the patterns you can draw out of them.

Now, let us say for example that this chart is about the percentage of transportations on the road at a given time.

We can conclude that cars are the MOST preferred mode of transportation and that there are STILL people who use bicycle and wheelbarrow although they are the LEAST liked.