- the suffix `.elc' or `.el'; don't accept just FILE unless
- it ends in one of those suffixes or includes a directory name.
-Return t if file exists. */)
+the suffix `.elc' or `.el'; don't accept just FILE unless
+it ends in one of those suffixes or includes a directory name.
+
+If this function fails to find a file, it may look for different
+representations of that file before trying another file.
+It does so by adding the non-empty suffixes in `load-file-rep-suffixes'
+to the file name. Emacs uses this feature mainly to find compressed
+versions of files when Auto Compression mode is enabled.
+
+The exact suffixes that this function tries out, in the exact order,
+are given by the value of the variable `load-file-rep-suffixes' if
+NOSUFFIX is non-nil and by the return value of the function
+`get-load-suffixes' if MUST-SUFFIX is non-nil. If both NOSUFFIX and
+MUST-SUFFIX are nil, this function first tries out the latter suffixes
+and then the former.
+
+Loading a file records its definitions, and its `provide' and
+`require' calls, in an element of `load-history' whose
+car is the file name loaded. See `load-history'.
+
+Return t if the file exists and loads successfully. */)