Linux kernel options
Linux also has official documentation on kernel.org and tldp.org
the kernel is large today, most of which can be configured to be compiled or not; there is a default configuration when compiling the kernel
most of the features you would expect can be included
run ELF binaries
various filesystem support
virtualization support
Android drivers
debugging options for kernel hacking
pseudo-filesystems
most drivers for common hardware (e.g., LED, USB, and network devices)
special hardware drivers (e.g., Steam controller, Nintendo Wii)
most of the options can be configured either to be included inside of the kernel image or as an external module
most of the features are available as kernel options
CONFIG_HID_GENERICenables support for generic devices such as mice, keyboards, joysticksyou can know what compile options is included from the kernel with
/proc/config.gzbut only ifCONFIG_IKCONFIG_PROCis includedCONFIG_HID_BATTERY_STRENGTHenables reporting battery strength
you can know what kernel options of the compiled kernel by looking at
/proc/config.gz(e.g.,gunzip --stdout /proc/config.gz | bat); though, it is only possible if compiled withCONFIG_IKCONFIG_PROCoption.