| archive/tar | Package tar implements access to tar archives. |
| compress/gzip | Package gzip implements reading and writing of gzip format compressed files, as specified in RFC 1952. |
| debug/pe | Package pe implements access to PE (Microsoft Windows Portable Executable) files. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| io | Package io provides basic interfaces to I/O primitives. |
| log | Package log implements a simple logging package. |
| math | Package math provides basic constants and mathematical functions. |
| net/http | Package http provides HTTP client and server implementations. |
| 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. |
| runtime | Package runtime contains operations that interact with Go's runtime system, such as functions to control goroutines. |
| syscall | Package syscall contains an interface to the low-level operating system primitives. |
| unsafe | Package unsafe contains operations that step around the type safety of Go programs. |