Gordon Cullen was a very smart and creative man who loved to draw and design things. He was especially interested in how cities and towns were built and how they could be made to look more beautiful and organized.
He thought that the way buildings were arranged and the way the streets and sidewalks were designed could make a big difference in how people felt and behaved in a city.
To explain this, he made lots of drawings and pictures that showed how different arrangements of buildings and roads could make a city look more inviting and pleasant.
People who saw his drawings and ideas really liked them, and they started to use his ideas to design cities and towns in a better way.
So, in short, Gordon Cullen was a really smart and artistic person who helped make our cities and towns look and feel nicer!