Bars show the number of cards for each mana value.
Each bar is segmented by color weight: the number of colored symbols that appear in the casting cost of all cards with that mana value.
Bars show the number of cards that can produce each color of mana.
Rainbow segments represent sources that produce mana of any color. Conditions, such as "of any color among permanents you control", are not considered.
Darker segments represent nonland sources. Any card with an activated mana ability is counted as a mana source.