JavaScript Interview Questions and Answers
Ques 11. 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.
Ques 12. What is negative infinity?
It's a number in JavaScript, derived by dividing negative number by zero.
Ques 13. What is this keyword?
It refers to the current object.
Ques 14. What is Javascript?
A scripting language is a simple, interpreted programming language.
Scripts are embedded as plain text, interpreted by application.
Simpler execution model: don't need compiler or development environment.
Saves bandwidth: source code is downloaded, not compiled executable.
Platform-independence: code interpreted by any script-enabled browser.
But: slower than compiled code, not as powerful/full-featured.
Ques 15. What is identifier in Javascript?
Identifier– The name of a variable (or function)
Starts with a letter, can contains digits & underscores
Case Sensitive!!
Should be meaningful to someone reading your code
Good: accountBalance, amountDue
Bad: bal, due,
Just plain wrong: 2bOrNotToBe, +var, total-value
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