What are the similarities and differences between timelines and flow charts

They both give the information that you need.

The similarities and differences between timelines and flow charts is that:

timelines show important dates throughout history, as well as flow charts show important organized main ideas. (That is one similarity).

flow charts show the comparisons between two main ideas and in the middle of the large circles that have the main ideas inside, the middle circle is a list of all the differences between the two main ideas. So pretty much what I'm trying to say is that, flow charts show the comparisons and differences between two main ideas, and timleines just only show main ideas throughout history. (That is one difference).