In [[Swift]], variable declarations are done using the `var` keyword. ```swift var x = 1 x = 2 ``` To declare constants, use `let`. Try to use constants as often as possible instead of variables, it is safer and allows Swift to include some optimizations in the code. ```swift let pi = 3.14 ``` When naming variables, you should use lower camel case (`playerName`). This is the expected case convention for all [[Swift]] elements except types and protocols (which use upper camel case).