The Botswana flag as seen below was officially adopted in September 30 1966, which is the official Independence Day.
What the Flag Symbolizes...
The colors of the flag (which are similar to those of the Botswana Coat of Arms) are the national colors and have a great significance to Batswana.
Black and White
The black and white indicate the harmony and respect that exists between the different groups of people or races found in Botswana.
Some people say that the black and white were also influenced by the colors of zebra , which is also found in the Botswana Coat of Arms.
The blue represent rain / water , which support the cattle and crops ,...both of which are a livelihood for Botswana.
The importance of rain is also depicted in the coat of arms under the motto "Pula" which means rain in Setswana.