| bytes | Package bytes implements functions for the manipulation of byte slices. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| go/doc | Package doc extracts source code documentation from a Go AST. |
| io | Package io provides basic interfaces to I/O primitives. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| reflect | Package reflect implements run-time reflection, allowing a program to manipulate objects with arbitrary types. |
| regexp | Package regexp implements regular expression search. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| syscall | Package syscall contains an interface to the low-level operating system primitives. |
| text/template | Package template implements data-driven templates for generating textual output. |