Hello, in the text of plotting New York high school locations on a city map, the below code is used

``````m.drawmapboundary(fill_color='#85A6D9')
m.drawcoastlines(color='#6D5F47', linewidth=.4)
m.drawrivers(color='#6D5F47', linewidth=.4)
``````

I am wondering what is the source of the color like ‘#85A6D9’. What does this sequence represent and how do we select the one that serves our purpose? Thank you!

Hi @cmusongyang: In future, please provide a question link as per these guidelines.

In computers, colours are represented using a combination of Red, Green and Blue or `RGB`. Each of these colours take up a byte of memory, which can be represented in `binary` which are `0`s and `1`s. A byte is made up of bits (or a series of 8 `0`s and `1`s). Humans came up with a number system called `Hexadecimal` or `hex` so that you don’t have to read binary which can be rather tedious, for a simpler and more compact version of the data stored or processed.

The first 2 characters of `#85A6D9`, which is `85` represents the hex value for red. `A6` represents the hex value for green and `D9` represents the hex value for blue. Based on the colour combination intensities, other colours are derived. You can try googling this and you get a cyan-ish colour as shown below.

If you want to learn more about this, I suggest that you check out the first lecture of CS50 here about how colours and other data are represented in computers.

I think its up to you to decide what colours you want to use, but of course I recommend using symbolic (like green for forests in the case of maps) or complementary colours when plotting visualisations.

Hope this helps!

Thank you, this is very informative!

Hi @cmusongyang:

If my reply helped you to understand the concept, kindly mark my reply as the solution. Thanks!