JavaScript - #getting

Why am I getting "URIError: URI malformed" in JavaScript?
Why am I getting 'Uncaught TypeError: Cannot read property 'value' of null' in JavaScript?
Why am I getting 'Uncaught ReferenceError: variableName is not defined'?
Why am I getting 'Uncaught QuotaExceededError' in web storage?
Why am I getting a 'TypeError' when trying to call a function?
Why am I getting 'ReferenceError: X is not defined' in JavaScript?