# OS ## OS **Status:**  **type:** `os` **Description:** The operating system (OS) on which the process represented by this resource is running. **Other Attributes:** > :warning: This entity definition contains attributes without a role. > Stable Entities MUST NOT have attributes without a defined role. | Attribute | Type | Description | Examples | [Requirement Level](https://opentelemetry.io/docs/specs/semconv/general/attribute-requirement-level/) | Stability | |---|---|---|---|---|---| | [`os.type`](/docs/registry/attributes/os.md) | string | The operating system type. | `windows`; `linux`; `darwin` | `Required` |  | | [`os.build_id`](/docs/registry/attributes/os.md) | string | Unique identifier for a particular build or compilation of the operating system. [1] | `TQ3C.230805.001.B2`; `20E247`; `22621` | `Recommended` |  | | [`os.description`](/docs/registry/attributes/os.md) | string | Human readable (not intended to be parsed) OS version information, like e.g. reported by `ver` or `lsb_release -a` commands. | `Microsoft Windows [Version 10.0.18363.778]`; `Ubuntu 18.04.1 LTS` | `Recommended` |  | | [`os.name`](/docs/registry/attributes/os.md) | string | Human readable operating system name. | `iOS`; `Android`; `Ubuntu` | `Recommended` |  | | [`os.version`](/docs/registry/attributes/os.md) | string | The version string of the operating system as defined in [Version Attributes](/docs/resource/README.md#version-attributes). | `14.2.1`; `18.04.1` | `Recommended` |  | **[1] `os.build_id`:** `build_id` values SHOULD be obtained from the following sources: | OS | Primary | Fallback | | ------- | ------- | ------- | | Windows | `CurrentBuildNumber` from registry `HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion` | - | | MacOS | `ProductBuildVersion` from `/System/Library/CoreServices/SystemVersion.plist` | `ProductBuildVersion` from `/System/Library/CoreServices/ServerVersion.plist` | | Linux | `BUILD_ID` from `/etc/os-release` | `BUILD_ID` from `/usr/lib/os-release`;
contents of `/proc/sys/kernel/osrelease`| --- `os.type` has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used. | Value | Description | Stability | |---|---|---| | `aix` | AIX (Advanced Interactive eXecutive) |  | | `darwin` | Apple Darwin |  | | `dragonflybsd` | DragonFly BSD |  | | `freebsd` | FreeBSD |  | | `hpux` | HP-UX (Hewlett Packard Unix) |  | | `linux` | Linux |  | | `netbsd` | NetBSD |  | | `openbsd` | OpenBSD |  | | `solaris` | SunOS, Oracle Solaris |  | | `windows` | Microsoft Windows |  | | `zos` | IBM z/OS |  |