# Foundations
Foundational types and functions.
Here, you'll find documentation for basic data types like [integers]($int) and
[strings]($str) as well as details about core computational functions.
## Definitions
- [`arguments`](/reference/library/foundations/arguments/) - Captured arguments to a function.
- [`array`](/reference/library/foundations/array/) - A sequence of values.
- [`assert`](/reference/library/foundations/assert/) - Ensures that a condition is fulfilled.
- [`auto`](/reference/library/foundations/auto/) - A value that indicates a smart default.
- [`bool`](/reference/library/foundations/bool/) - A type with two states.
- [`bytes`](/reference/library/foundations/bytes/) - A sequence of bytes.
- [calc](/reference/library/foundations/calc/) - Module for calculations and processing of numeric values.
- [`content`](/reference/library/foundations/content/) - A piece of document content.
- [`datetime`](/reference/library/foundations/datetime/) - Represents a date, a time, or a combination of both.
- [`decimal`](/reference/library/foundations/decimal/) - A fixed-point decimal number type.
- [`dictionary`](/reference/library/foundations/dictionary/) - A map from string keys to values.
- [`duration`](/reference/library/foundations/duration/) - Represents a positive or negative span of time.
- [`eval`](/reference/library/foundations/eval/) - Evaluates a string as Typst code.
- [`float`](/reference/library/foundations/float/) - A floating-point number.
- [`function`](/reference/library/foundations/function/) - A mapping from argument values to a return value.
- [`int`](/reference/library/foundations/int/) - A whole number.
- [`label`](/reference/library/foundations/label/) - A label for an element.
- [`module`](/reference/library/foundations/module/) - A collection of variables and functions that are commonly related to
- [`none`](/reference/library/foundations/none/) - A value that indicates the absence of any other value.
- [`panic`](/reference/library/foundations/panic/) - Fails with an error.
- [`plugin`](/reference/library/foundations/plugin/) - Loads a WebAssembly module.
- [`regex`](/reference/library/foundations/regex/) - A regular expression.
- [`repr`](/reference/library/foundations/repr/) - Returns the string representation of a value.
- [`selector`](/reference/library/foundations/selector/) - A filter for selecting elements within the document.
- [`str`](/reference/library/foundations/str/) - A sequence of Unicode codepoints.
- [`symbol`](/reference/library/foundations/symbol/) - A Unicode symbol.
- [sys](/reference/library/foundations/sys/) - Module for system interactions.
- [`target`](/reference/library/foundations/target/) - Returns the current export target.
- [`type`](/reference/library/foundations/type/) - Describes a kind of value.
- [`version`](/reference/library/foundations/version/) - A version with an arbitrary number of components.