Package ioutil implements some I/O utility functions.

Package log implements a simple logging package.

Package slog provides structured logging, in which log records include a message, a severity level, and various other attributes expressed as key-value pairs.

Package syslog provides a simple interface to the system log service.

Package maps defines various functions useful with maps of any type.

Package math provides basic constants and mathematical functions.

Package big implements arbitrary-precision arithmetic (big numbers).

Package bits implements bit counting and manipulation functions for the predeclared unsigned integer types.

Package cmplx provides basic constants and mathematical functions for complex numbers.

Package rand implements pseudo-random number generators suitable for tasks such as simulation, but it should not be used for security-sensitive work.