# root package

#### package root

This is the documentation for the Scala standard library.

#### Package structure

The scala package contains core types.

`scala.collection` and its subpackages contain a collections framework with higher-order functions for manipulation. Both `scala.collection.immutable` and `scala.collection.mutable` data structures are available, with immutable as the default. The `scala.collection.parallel` collections provide automatic parallel operation.

Other important packages include:

- `scala.actors` - Concurrency framework inspired by Erlang.
- `scala.io` - Input and output.
- `scala.math` - Basic math functions and additional numeric types.
- `scala.sys` - Interaction with other processes and the operating system.
- `scala.util.matching` - Pattern matching in text using regular expressions.
- `scala.util.parsing.combinator` - Composable combinators for parsing.
- `scala.xml` - XML parsing, manipulation, and serialization.

Many other packages exist. See the complete list on the left.

#### Automatic imports

Identifiers in the scala package and the `scala.Predef` object are always in scope by default.

Some of these identifiers are type aliases provided as shortcuts to commonly used classes. For example, `List` is an alias for `scala.collection.immutable.List`.

Other aliases refer to classes provided by the underlying platform. For example, on the JVM, `String` is an alias for `java.lang.String`.

Visibility

1. Public
2. All

### Value Members

1. #### package scala

   Core Scala types.

### Ungrouped