Interview questions and answers : JavaScript
What’s relationship between JavaScript and ECMAScript? - ECMAScript is yet another name for JavaScript (other names include LiveScript). The current JavaScript that you see supported in browsers is ECMAScript revision 3. What are JavaScript types? - Number, String, Boolean, Function, Object, Null, Undefined. How do you convert numbers between different bases in JavaScript? - Use the parseInt() function, that takes a string as the first parameter, and the base as a second parameter. So to convert hexadecimal 3F to decimal, use parseInt ("3F", 16); What does isNaN function do? - Return true if the argument is not a number. What is negative infinity? - It’s a number in JavaScript, derived by dividing negative number by zero. What boolean operators does JavaScript support? - &&, || and ! What does "1"+2+4 evaluate to? - Since 1 is a string, everything is a string, so the result is 124. How about 2+5+"8"? - Since 2 and 5 are intege