In short: Each cab journey is represented by a point, the first image showing pick-ups and the second showing drop-offs.
Description: This image is a simple geographic representation of all pick-up and drop-offs of each taxi journey in NYC at the beginning of 2015. The color palette was chosen to emphasize a biological nature in the image akin to a petri-dish, or some kind of cell migration under a microscope. Maps often can appear impersonal and this is a study in response to this. The airport links have a distinctly biological appearance. NYC was chosen as the geography is very familiar and synonymous with the yellow cab.
Point of interest: A nice artifact is that color appears in areas where no taxi pick-up or drop-off could happen (e.g. in water or areas in Central Park), this is likely due to GPS confusion caused by the tall buildings.
Technical: 6 months of yellow cab trip data for (Jan-Jun 2015) available at https://nycopendata.socrata.com/. ~70 million taxi journeys. The image shows a linear 2D image of all GPS Latitude and Longitude coordinates of taxi pick-ups and drop-offs for all journeys within the limits of the image. The color scale is a linear count with slight off-set on the maximum to allow saturation and emphasis lower-count areas.