| 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. |
| math | Package math provides basic constants and mathematical functions. |
| math/big | Package big implements arbitrary-precision arithmetic (big numbers). |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |