What is the difference between an avenue and a street?

Historically, an avenue was a road that led to a particular building, while a street was any roadway in a city. Avenues were lined with trees.

In some cities, such as New York, streets running one direction (such as north-south) are called avenues while streets running the other direction are known as streets. In other cities, such as Chicago, there is no distinction between streets and avenues.