string.toUpperCase() and string.toLowerCase()

var stringName = "hOwdY"

stringName.toUpperCase()
// result is "HOWDY"

stringName.toLowerCase()
// result is "howdy"

The first function "toUpper()", takes the value of the text input and converts it to uppercase using the toUpperCase() method.

The second function, "toLower()" takes the value of the text input and converts it to lowercase using the toLowerCase() method.

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