dired-omit-extensions

dired-omit-extensions is a variable defined in `dired-x.el'.
Its value is

(".o" "~" ".bin" ".lbin" ".so" ".a" ".ln" ".blg" ".bbl" ".elc" ".lof" ".glo" ".idx" ".lot" ".svn/" ".hg/" ".git/" ".bzr/" "CVS/" "_darcs/" "_MTN/" ".fmt" ".tfm" ".class" ".fas" ".lib" ".mem" ".x86f" ".sparcf" ".dfsl" ".pfsl" ".d64fsl" ".p64fsl" ".lx64fsl" ".lx32fsl" ".dx64fsl" ".dx32fsl" ".fx64fsl" ".fx32fsl" ".sx64fsl" ".sx32fsl" ".wx64fsl" ".wx32fsl" ".fasl" ".ufsl" ".fsl" ".dxl" ".lo" ".la" ".gmo" ".mo" ".toc" ".aux" ".cp" ".fn" ".ky" ".pg" ".tp" ".cps" ".fns" ".kys" ".pgs" ".tps" ".vrs" ".pyc" ".pyo" ".idx" ".lof" ".lot" ".glo" ".blg" ".bbl" ".cp" ".cps" ".fn" ".fns" ".ky" ".kys" ".pg" ".pgs" ".tp" ".tps" ".vr" ".vrs")

Documentation:
If non-nil, a list of extensions (strings) to omit from Dired listings.
Defaults to elements of `completion-ignored-extensions',
`dired-latex-unclean-extensions', `dired-bibtex-unclean-extensions', and
`dired-texinfo-unclean-extensions'.

See interactive function `dired-omit-mode' (M-x dired-omit-mode) and
variables `dired-omit-mode' and `dired-omit-files'.

You can customize this variable.