| bytes | Package bytes implements functions for the manipulation of byte slices. |
| context | Package context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes. |
| errors | Package errors implements functions to manipulate errors. |
| flag | Package flag implements command-line flag parsing. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| internal/goexperiment | Package goexperiment implements support for toolchain experiments. |
| internal/race | Package race contains helper functions for manually instrumenting code for the race detector. |
| internal/syscall/windows | |
| internal/sysinfo | Package sysinfo implements high level hardware information gathering that can be used for debugging or information purposes. |
| io | Package io provides basic interfaces to I/O primitives. |
| math | Package math provides basic constants and mathematical functions. |
| math/bits | Package bits implements bit counting and manipulation functions for the predeclared unsigned integer types. |
| math/rand | Package rand implements pseudo-random number generators suitable for tasks such as simulation, but it should not be used for security-sensitive work. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| 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. |
| runtime/debug | Package debug contains facilities for programs to debug themselves while they are running. |
| runtime/trace | Package trace contains facilities for programs to generate traces for the Go execution tracer. |
| slices | Package slices defines various functions useful with slices of any type. |
| strconv | Package strconv implements conversions to and from string representations of basic data types. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |
| sync/atomic | Package atomic provides low-level atomic memory primitives useful for implementing synchronization algorithms. |
| syscall | Package syscall contains an interface to the low-level operating system primitives. |
| time | Package time provides functionality for measuring and displaying time. |
| 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. |
| unsafe | Package unsafe contains operations that step around the type safety of Go programs. |