| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| internal/fmtsort | Package fmtsort provides a general stable ordering mechanism for maps, on behalf of the fmt and text/template packages. |
| io | Package io provides basic interfaces to I/O primitives. |
| io/fs | Package fs defines basic interfaces to a file system. |
| maps | Package maps defines various functions useful with maps of any type. |
| net/url | Package url parses URLs and implements query escaping. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| path | Package path implements utility routines for manipulating slash-separated paths. |
| path/filepath | Package filepath implements utility routines for manipulating filename paths in a way compatible with the target operating system-defined file paths. |
| reflect | Package reflect implements run-time reflection, allowing a program to manipulate objects with arbitrary types. |
| runtime | Package runtime contains operations that interact with Go's runtime system, such as functions to control goroutines. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |
| text/template/parse | Package parse builds parse trees for templates as defined by text/template and html/template. |
| unicode | Package unicode provides data and functions to test some properties of Unicode code points. |
| unicode/utf8 | Package utf8 implements functions and constants to support text encoded in UTF-8. |