Es6 introduced 'let' and 'const' to register variables. By default use 'let' to indicate that the variable can mutate or be reassigned, otherwise use 'const'. The use of 'var' has been limited to use in the global scope.
#javascript#es6
leta="5"// Use by defaultconstday="Monday"// Assume that the value doesn't changevartheme="sunrise"// Mainly used for global variables