When the minibuffer is in use, it appears in the echo area, with a cursor. The minibuffer starts with a prompt, usually ending with a colon. The prompt states what kind of input is expected, and how it will be used. The prompt is highlighted using the minibuffer-prompt face (Faces). The simplest way to enter a minibuffer argument is to type the text, then RET to submit the argument and exit the minibuffer. Alternatively, you can type C-g to exit the minibuffer by canceling the command asking for the argument (Quitting). Sometimes, the prompt shows a default argument, inside parentheses before the colon. This default will be used as the argument if you just type RET. For example, commands that read buffer names usually show a buffer name as the default; you can type RET to operate on that default buffer. You can customize how the default argument is shown with the user option minibuffer-default-prompt-format. If you enable Minibuffer Electric Default mode, a global minor mode, Emacs hides the default argument as soon as you modify the contents of the minibuffer (since typing RET would no longer submit that default). If you ever bring back the original minibuffer text, the prompt again shows the default. To enable this minor mode, type M-x minibuffer-electric-default-mode. Since the minibuffer appears in the echo area, it can conflict with other uses of the echo area. If an error message or an informative message is emitted while the minibuffer is active, the message is displayed in brackets after the minibuffer text for a few seconds, or until you type something; then the message disappears. While the minibuffer is in use, Emacs does not echo keystrokes. While using the minibuffer, you can switch to a different frame, perhaps to note text you need to enter (Frame Commands). By default, the active minibuffer moves to this new frame. If you set the user option minibuffer-follows-selected-frame to nil, then the minibuffer stays in the frame where you opened it, and you must switch back to that frame in order to complete (or abort) the current command. If you set that option to a value which is neither nil nor t, the minibuffer moves frame only after a recursive minibuffer has been opened in the current command (Recursive Mini). This option is mainly to retain (approximately) the behavior prior to Emacs 28.1. Note that the effect of the command, when you finally finish using the minibuffer, always takes place in the frame where you first opened it. The sole exception is that when that frame no longer exists, the action takes place in the currently selected frame.

Commands such as C-x C-f (find-file) use the minibuffer to read a file name argument (Basic Files). When the minibuffer is used to read a file name, it typically starts out with some initial text ending in a slash. This is the default directory. For example, it may start out like this:

Find file: /u2/emacs/src/

Here, Find file: is the prompt and /u2/emacs/src/ is the default directory. If you now type buffer.c as input, that specifies the file /u2/emacs/src/buffer.c. File Names, for information about the default directory. Alternative defaults for the file name you may want are available by typing M-n, see Minibuffer History. You can specify a file in the parent directory with ..: /a/b/../foo.el is equivalent to /a/foo.el. Alternatively, you can use M-DEL to kill directory names backwards (Words). To specify a file in a completely different directory, you can kill the entire default with C-a C-k (Minibuffer Edit). Alternatively, you can ignore the default, and enter an absolute file name starting with a slash or a tilde after the default directory. For example, you can specify /etc/termcap as follows:

Find file: /u2/emacs/src//etc/termcap

A double slash causes Emacs to ignore everything before the second slash in the pair. In the example above, /u2/emacs/src/ is ignored, so the argument you supplied is /etc/termcap. The ignored part of the file name is dimmed if the terminal allows it. (To disable this dimming, turn off File Name Shadow mode with the command M-x file-name-shadow-mode.) When completing remote file names (Remote Files), a double slash behaves slightly differently: it causes Emacs to ignore only the file-name part, leaving the rest (method, host and username, etc.) intact. Typing three slashes in a row ignores everything in remote file names. File name completion. Emacs interprets ~/ as your home directory. Thus, ~/foo/bar.txt specifies a file named bar.txt, inside a directory named foo, which is in turn located in your home directory. In addition, ~user-id/ means the home directory of a user whose login name is user-id. Any leading directory name in front of the ~ is ignored: thus, /u2/emacs/~/foo/bar.txt is equivalent to ~/foo/bar.txt. On MS-Windows and MS-DOS systems, where a user doesn't always have a home directory, Emacs uses several alternatives. For MS-Windows, see Windows HOME; for MS-DOS, see MS-DOS File Names. On these systems, the ~user-id/ construct is supported only for the current user, i.e., only if user-id is the current user's login name. To prevent Emacs from inserting the default directory when reading file names, change the variable insert-default-directory to nil. In that case, the minibuffer starts out empty. Nonetheless, relative file name arguments are still interpreted based on the same default directory. You can also enter remote file names in the minibuffer. Remote Files.

The minibuffer is an Emacs buffer, albeit a peculiar one, and the usual Emacs commands are available for editing the argument text. (The prompt, however, is read-only, and cannot be changed.) Since RET in the minibuffer submits the argument, you can't use it to insert a newline. You can do that with C-q C-j, which inserts a C-j control character, which is formally equivalent to a newline character (Inserting Text). Alternatively, you can use the C-o (open-line) command (Blank Lines). Inside a minibuffer, the keys TAB, SPC, and ? are often bound to completion commands, which allow you to easily fill in the desired text without typing all of it. Completion. As with RET, you can use C-q to insert a TAB, SPC, or ? character. If you want to make SPC and ? insert normally instead of starting completion, you can put the following in your init file:

(keymap-unset minibuffer-local-completion-map "SPC")
(keymap-unset minibuffer-local-completion-map "?")

For convenience, C-a (move-beginning-of-line) in a minibuffer moves point to the beginning of the argument text, not the beginning of the prompt. For example, this allows you to erase the entire argument with C-a C-k. When the minibuffer is active, the echo area is treated much like an ordinary Emacs window. For instance, you can switch to another window (with C-x o), edit text there, then return to the minibuffer window to finish the argument. You can even kill text in another window, return to the minibuffer window, and yank the text into the argument. There are some restrictions on the minibuffer window, however: for instance, you cannot split it. Windows. Normally, the minibuffer window occupies a single screen line. However, if you add two or more lines' worth of text into the minibuffer, it expands automatically to accommodate the text. The variable resize-mini-windows controls the resizing of the minibuffer. The default value is grow-only, which means the behavior we have just described. If the value is t, the minibuffer window will also shrink automatically if you remove some lines of text from the minibuffer, down to a minimum of one screen line. If the value is nil, the minibuffer window never changes size automatically, but you can use the usual window-resizing commands on it (Windows). The variable max-mini-window-height controls the maximum height for resizing the minibuffer window. A floating-point number specifies a fraction of the frame's height; an integer specifies the maximum number of lines; nil means do not resize the minibuffer window automatically. The default value is 0.25. The C-M-v command in the minibuffer scrolls the help text from commands that display help text of any sort in another window. You can also scroll the help text with M-PageUp and M-PageDown (or, equivalently, M-prior and M-next). This is especially useful with long lists of possible completions. Other Window. Emacs normally disallows most commands that use the minibuffer while the minibuffer is active. To allow such commands in the minibuffer, set the variable enable-recursive-minibuffers to t. You might need also to enable minibuffer-depth-indicate-mode to show the current recursion depth in the minibuffer prompt on recursive use of the minibuffer. When active, the minibuffer is usually in minibuffer-mode. This is an internal Emacs mode without any special features. When not active, the minibuffer is in minibuffer-inactive-mode, and clicking mouse-1 there shows the *Messages* buffer. If you use a dedicated frame for minibuffers, Emacs also recognizes certain keys there, for example, n to make a new frame.

You can often use a feature called completion to help enter arguments. This means that after you type part of the argument, Emacs can fill in the rest, or some of it, based on what was typed so far. When completion is available, certain keys (usually TAB, RET, and SPC) are rebound in the minibuffer to special completion commands (Completion Commands). These commands attempt to complete the text in the minibuffer, based on a set of completion alternatives provided by the command that requested the argument. You can usually type ? to see a list of completion alternatives. Although completion is usually done in the minibuffer, the feature is sometimes available in ordinary buffers too. Symbol Completion.

Everything you type in the minibuffer is saved in a minibuffer history list so you can easily use it again later. This includes completion candidates (such as file names, buffer names, command names, etc.) and any other kind of minibuffer input. You can use the following commands to quickly fetch an earlier or alternative response into the minibuffer:

M-p

Move to the previous item in the minibuffer history, an earlier argument (previous-history-element).

M-n

Move to the next item in the minibuffer history (next-history-element).

UP, DOWN

Like M-p and M-n, but move to the previous or next line of a multi-line item before going to the previous history item (previous-line-or-history-element and next-line-or-history-element) .

M-r regexp RET

Move to an earlier item in the minibuffer history that matches regexp (previous-matching-history-element).

M-s regexp RET

Move to a later item in the minibuffer history that matches regexp (next-matching-history-element).

While in the minibuffer, M-p (previous-history-element) moves through the minibuffer history list, one item at a time. Each M-p fetches an earlier item from the history list into the minibuffer, replacing its existing contents. Typing M-n (next-history-element) moves through the minibuffer history list in the opposite direction, fetching later entries into the minibuffer. If you type M-n in the minibuffer when there are no later entries in the minibuffer history (e.g., if you haven't previously typed M-p), Emacs tries fetching from a list of default arguments: values that you are likely to enter. You can think of this as moving through the "future history". The "future history" for file names includes several possible alternatives you may find useful, such as the file name or the URL at point in the current buffer. The defaults put into the "future history" in this case are controlled by the functions mentioned in the value of the option file-name-at-point-functions. By default, its value invokes the ffap package (FFAP), which tries to guess the default file or URL from the text around point. To disable this guessing, customize the option to a nil value, then the "future history" of file names will include only the file, if any, visited by the current buffer, and the default directory. The arrow keys UP and DOWN work like M-p and M-n, but if the current history item is longer than a single line, they allow you to move to the previous or next line of the current history item before going to the previous or next history item. If you edit the text inserted by the M-p or M-n minibuffer history commands, this does not change its entry in the history list. However, the edited argument does go at the end of the history list when you submit it. You can use M-r (previous-matching-history-element) to search through older elements in the history list, and M-s (next-matching-history-element) to search through newer entries. Each of these commands asks for a regular expression as an argument, and fetches the first matching entry into the minibuffer. Regexps, for an explanation of regular expressions. A numeric prefix argument n means to fetch the /n/th matching entry. These commands are unusual, in that they use the minibuffer to read the regular expression argument, even though they are invoked from the minibuffer. An upper-case letter in the regular expression makes the search case-sensitive (Lax Search). You can also search through the history using an incremental search. Isearch Minibuffer. Emacs keeps separate history lists for several different kinds of arguments. For example, there is a list for file names, used by all the commands that read file names. Other history lists include buffer names, command names (used by M-x), and command arguments (used by commands like query-replace). The variable history-length specifies the maximum length of a minibuffer history list; adding a new element deletes the oldest element if the list gets too long. If the value is t, there is no maximum length. The variable history-delete-duplicates specifies whether to delete duplicates in history. If it is non-nil, adding a new element deletes from the list all other elements that are equal to it. The default is nil.

Every command that uses the minibuffer once is recorded on a special history list, the command history, together with the values of its arguments, so that you can repeat the entire command. In particular, every use of M-x is recorded there, since M-x uses the minibuffer to read the command name.

C-x ESC ESC

Re-execute a recent minibuffer command from the command history (repeat-complex-command).

M-x list-command-history

Display the entire command history, showing all the commands C-x ESC ESC can repeat, most recent first.

C-x ESC ESC re-executes a recent command that used the minibuffer. With no argument, it repeats the last such command. A numeric argument specifies which command to repeat; 1 means the last one, 2 the previous, and so on. C-x ESC ESC works by turning the previous command into a Lisp expression and then entering a minibuffer initialized with the text for that expression. Even if you don't know Lisp, it will probably be obvious which command is displayed for repetition. If you type just RET, that repeats the command unchanged. You can also change the command by editing the Lisp expression before you execute it. The executed command is added to the front of the command history unless it is identical to the most recent item. Once inside the minibuffer for C-x ESC ESC, you can use the usual minibuffer history commands (Minibuffer History) to move through the history list. After finding the desired previous command, you can edit its expression as usual and then execute it by typing RET. Incremental search does not, strictly speaking, use the minibuffer. Therefore, although it behaves like a complex command, it normally does not appear in the history list for C-x ESC ESC. You can make incremental search commands appear in the history by setting isearch-resume-in-command-history to a non-nil value. Incremental Search. The list of previous minibuffer-using commands is stored as a Lisp list in the variable command-history. Each element is a Lisp expression that describes one command and its arguments. Lisp programs can re-execute a command by calling eval with the command-history element.

Sometimes, you may need to enter a password into Emacs. For instance, when you tell Emacs to visit a file on another machine via a network protocol such as FTP, you often need to supply a password to gain access to the machine (Remote Files). Entering a password is similar to using a minibuffer. Emacs displays a prompt in the echo area (such as Password:); after you type the required password, press RET to submit it. To prevent others from seeing your password, every character you type is displayed as an asterisk (*) instead of its usual form. Most of the features and commands associated with the minibuffer cannot be used when entering a password. There is no history or completion, and you cannot change windows or perform any other action with Emacs until you have submitted the password. While you are typing the password, you may press DEL to delete backwards, removing the last character entered. C-u deletes everything you have typed so far. C-g quits the password prompt (Quitting). C-y inserts the current kill into the password (Killing). TAB toggles the visibility of the password. You may type either RET or ESC to submit the password. Any other self-inserting character key inserts the associated character into the password, and all other input is ignored. There is also an icon in the mode line indicating the password visibility. Clicking mouse-1 on it toggles the password visibility as well.

An Emacs command may require you to answer a yes-or-no question during the course of its execution. Such queries come in two main varieties. For the first type of yes-or-no query, the prompt ends with (y or n). You answer the query by typing a single key, either y or n, which immediately exits the minibuffer and delivers the response. For example, if you type C-x C-w (write-file) to save a buffer, and enter the name of an existing file, Emacs issues a prompt like this:

File ‘foo.el’ exists; overwrite? (y or n)

The second type of yes-or-no query is typically employed if giving the wrong answer would have serious consequences; it thus features a longer prompt ending with (yes or no) (or the value of yes-or-no-prompt if you've customized that). For example, if you invoke C-x k (kill-buffer) on a file-visiting buffer with unsaved changes, Emacs activates the minibuffer with a prompt like this:

Buffer foo.el modified; kill anyway? (yes or no)

To answer, you must type yes or no into the minibuffer, followed by RET. With both types of yes-or-no query the minibuffer behaves as described in the previous sections; you can recenter the selected window with C-l, scroll that window (C-v or PageDown scrolls forward, M-v or PageUp scrolls backward), switch to another window with C-x o, use the history commands M-p and M-n, etc. Type C-g to dismiss the query, and quit the minibuffer and the querying command (Quitting).