The commands which move between and inside nodes allow you to read the entire manual or its large portions. But what if you need to find some information in the manual as fast as you can, and you don’t know or don’t remember in what node to look for it? This need arises when you use a manual as a reference, or when it is impractical to read the entire manual before you start using the programs it describes.
Info has powerful searching facilities that let you find things quickly. You can search either the manual text or its indices.
The s command allows you to search a whole Info file for a string. It switches to the next node if and when that is necessary. You type s followed by the string to search for, terminated by RET. To search for the same string again, just s followed by RET will do. The file’s nodes are scanned in the order they are in the file, which has no necessary relationship to the order that they may be in the tree structure of menus and ‘next’ pointers. But normally the two orders are not very different. In any case, you can always look at the mode line to find out what node you have reached, if the header is not visible (this can happen, because s puts your cursor at the occurrence of the string, not at the beginning of the node).
Instead of using s in Emacs Info and in the stand-alone Info,
you can use an incremental search started with C-s or C-r.
It can search through multiple Info nodes. See Incremental Search in The GNU Emacs Manual. In Emacs, you can disable this behavior
by setting the variable Info-isearch-search to nil
(see Emacs Info-mode Variables).