Humans have always sought to understand & explain our world. Weather and climate are no exception. As our understanding of weather patterns and longer term climate patterns has increased, we have devised a classification scheme to summarize planetary climate zones.
Global climate zones are based on specific lines of latitude--the Arctic and Antarctic Circles at 66.5 degrees north and south respectively, the Tropic of Capricorn at 23.5 degrees south, and the Tropic of Cancer at 23.5 degrees north.
The location between the two tropics is called the low latitudes. Most of the climates in the low latitudes are tropical, with high rainfall, high humidity, and little temperature variation.
Between the tropics and the Arctic and Antarctic circles lie what is known as the middle latitudes, with mostly temperate climates. Temperate climates have four identifiable seasons, with warm summers and colder winters. Rainfall patterns are uniform.
The high latitudes refer to the regions between the Artic and Antarctic circles and the poles. The high latitudes have polar climates. Polar climates have very long and cold winters, with only slightly warmer summers. Most precipitation comes in the form of snow.
This broad climatic classification supplies an overall perspective of global weather. But variations do exist within these broad zones. Sometimes, the global climate zones are divided into maritime and continental regions. The weather over coastal areas (maritime) differs greatly from the weather over inland areas (continental). But even this sub-classification doesn't account for the impact of mountain ranges and ocean currents.
There will obviously be local variations within these global climate zones. Sometimes the variations are long term and result in climatic anomalies. But overall, global climatic zones provide us with a useful overview of global weather patterns, and give us at least a hint regarding the types of weather to expect.