TypeErrorTypeError
A value is not of the expected type. This is the most common JavaScript error, occurring when an operation encounters a value of the wrong type.
SyntaxError: Identifier has already been declaredA variable with the same name was declared twice in the same scope using let or const.
You declared a variable with let or const that already exists in the same scope. Unlike var, let and const do not allow redeclaration. This often happens when copying code or in files with multiple declarations.
Rename one of the duplicate declarations. If you want to reassign, use assignment (=) instead of redeclaring. Check for duplicate imports or conflicting variable names from different code blocks.
let x = 1; let x = 2; // SyntaxErrorTypeErrorA value is not of the expected type. This is the most common JavaScript error, occurring when an operation encounters a value of the wrong type.
TypeError: x is not iterableA value that is not iterable was used where an iterable was expected, such as in a for...of loop or spread operator.
ReferenceErrorA reference was made to a variable that does not exist in the current scope.
ECONNREFUSEDThe connection was refused because no server is listening on the target address and port.
ERR_ASYNC_CALLBACKA non-function value was passed where an async callback was expected.
ERR_SOCKET_BAD_PORTAn invalid port number was specified for a network operation.