Using Sass variable you assign a value to a name that begins with $, and then you can refer to that name instead of repeating the value over and over again.
Global variables can be accessed anywhere, whereas Local variables can only be accessed within the block they were declared.
CSS has variables of its own, which are totally different than Sass variables.
|Sass Variable||CSS Variable|
|Sass variables are all compiled away by Sass.||CSS variables are included in the CSS output.|
|Sass variables only have one value at a time.||CSS variables can have different values for different elements.|
|Sass variables are imperative, which means if you use a variable and then change its value, the earlier use will stay the same.||CSS variables are declarative, which means if you change the value, it’ll affect both earlier uses and later uses.|