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## 1. `Error` - the base error class

This is the **universal type** that all other errors inherit from.
If you are not sure which error type fits, you can just use `Error`.

```javascript
throw new Error("Something went wrong!");
```

Properties:

- `name` - the error's name (`"Error"`)
- `message` - the description
- `stack` - the stack trace (shows where the error occurred)

## 2. `ReferenceError` - a reference error

Occurs when there is a **reference to a non-existent variable** or a property that is not accessible in the current scope.

```javascript
console.log(x); // ReferenceError: x is not defined
```

It can also occur from **incorrect use of** `this`.

## 3. `TypeError` - a type error

Occurs when an operation is applied to a **value of the wrong type**,
or when something that is not a function is called.

```javascript
let n = null;
console.log(n.toString()); // TypeError: Cannot read properties of null
```

```javascript
let func = 123;
func(); // TypeError: func is not a function
```

## 4. `RangeError` - out of the allowed range

Occurs when a passed value is **outside the allowed range**.

```javascript
new Array(-5); // RangeError: Invalid array length
```

```javascript
(123.456).toFixed(200); // RangeError: toFixed() digits argument must be between 0 and 100
```

## 5. `SyntaxError` - a syntax error

An error caused by **violating JavaScript syntax**.
The engine cannot "parse" the code, so the program **does not even start**.

```javascript
eval("if (true { console.log('hi'); }");
// SyntaxError: Unexpected token '{'
```

> Such errors cannot be caught with `try...catch`,
> because they occur **before execution even begins**.

## 6. `URIError` - an error in URI functions

Occurs if the `encodeURI()`, `decodeURI()`, `encodeURIComponent()`, or `decodeURIComponent()` functions receive invalid data.

```javascript
decodeURIComponent("%");
// URIError: URI malformed
```

## 7. `EvalError` - an error from using `eval()`

Rare in modern implementations.
Originally used when `eval()` was used incorrectly.

```javascript
throw new EvalError("Incorrect use of eval()");
```

## 8. (Additionally) `AggregateError` - a set of errors

Occurs when **a single operation returns several errors at once**, for example with `Promise.any()`.

```javascript
Promise.any([
  Promise.reject(new Error("Error 1")),
  Promise.reject(new Error("Error 2")),
]).catch(e => console.log(e.errors));
```

Output:

```javascript
[Error: Error 1, Error: Error 2]
```

## 9. Custom errors

You can create your own error classes by extending `Error`:

```javascript
class ValidationError extends Error {
  constructor(message) {
    super(message);
    this.name = "ValidationError";
  }
}

throw new ValidationError("Invalid email");
```

Output:

```javascript
ValidationError: Invalid email
```

## Summary table

| Error type | When it occurs | Example |
|---|---|---|
| **Error** | The base class for all errors | `throw new Error("Error!")` |
| **ReferenceError** | A variable is not defined | `console.log(x)` |
| **TypeError** | The value has the wrong type | `null.toString()` |
| **RangeError** | A value is outside the allowed range | `new Array(-1)` |
| **SyntaxError** | A syntax error | `eval("if (true {")` |
| **URIError** | An error encoding/decoding a URI | `decodeURI("%")` |
| **EvalError** | An `eval()` error (rarely used) | `throw new EvalError()` |
| **AggregateError** | Several errors at once | `Promise.any([...])` |

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