type

Describe a command, for each name, indicate how it would be interpreted if used as
a command name.

SYNTAX
      type [-atp] [name ...]

OPTIONS
   If the `-t' option is used, type prints a single word which is one of:
      `alias'    (shell alias)
      `function' (shell function)
      `builtin'  (shell builtin)
      `file'     (disk file)
      `keyword'  (shell reserved word) 

   If the `-p' option is used, type either returns the name of the disk file that 
   would be executed, or nothing if `-t' would not return `file'.
      
   If the `-a' option is used, type returns all of the places that contain an 
   executable named file. This includes aliases and functions, if and only if the 
   `-p' option is not also used.

The return status is zero if any of the names are found, non-zero otherwise.

`type' is a BASH builtin command.

Related commands:

builtin - Run a shell builtin
env - Display, set, or remove environment variables
echo - Display message on screen
export - Set an environment variable
function - Define Function Macros
readonly - Mark variables/functions as readonly
set - Manipulate shell variables and functions