# catch

Continues an observable sequence that is terminated by an exception with the next observable sequence. There is an alias for this method `catchException` for browsers \<IE9

## Arguments

1. `second` *(`Observable`)*: A second observable sequence used to produce results when an error occurred in the first sequence.
2. `handler` *(`Function`)*: Exception handler function that returns an observable sequence given the error that occurred in the first sequence

## Returns

*(`Observable`)*: An observable sequence containing the first sequence's elements, followed by the elements of the handler sequence in case an exception occurred.

## Example

### Using a second observable

### Using a handler function


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