For information on a specific language environment (see Language Environments), type
C-h L (
describe-language-environment). This displays a help buffer describing the languages supported by the language environment, and listing the associated character sets, coding systems, and input methods, as well as some sample text for that language environment.
C-h h (
view-hello-file) displays the file
etc/HELLO, which demonstrates various character sets by showing how to say “hello" in many languages.
C-h I (
describe-input-method) describes an input method—either a specified input method, or by default the input method currently in use. See Input Methods.
C-h C (
describe-coding-system) describes coding systems—either a specified coding system, or the ones currently in use. See Coding Systems.