| encoding/binary | Package binary implements simple translation between numbers and byte sequences and encoding and decoding of varints. |
| 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/saferio | Package saferio provides I/O functions that avoid allocating large amounts of memory unnecessarily. |
| io | Package io provides basic interfaces to I/O primitives. |
| os | Package os provides a platform-independent interface to operating system functionality. |