Live Demo: Make the First Character of a String Uppercase in JavaScript

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Make the First Character of a String Uppercase in JavaScript</title>
</head>
<body>
 Note: Click the "Show Output" button or refresh the page to run the test again.
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	<script>
 // Define function to capitalize the first letter of a string
 function capitalizeFirstLetter(string){
 return string.charAt(0).toUpperCase() + string.slice(1);
 }
 
 // Calling function and display the result
 var str1 = 'hi there!';
 str1 = capitalizeFirstLetter(str1);
 document.write('' + str1 + ''); // Print: Hi there!
 
 var str2 = 'the Gods must be crazy.';
 str2 = capitalizeFirstLetter(str2);
 document.write('' + str2 + ''); // Print: The Gods must be crazy.
 
 var str3 = '/app/index.html';
 str2 = capitalizeFirstLetter(str3);
 document.write('' + str3 + ''); // Print: /app/index.html
 </script> 
</body>
</html>