You're looking for white vinegar (also known as distilled vinegar), which is sold in most supermarkets.
The cleaning powers of vinegar are great against loads of different types of marks, and once you've given your clothes a spin in the machine, they should come out stain-free!.
If you're struggling to get a nasty stain out of your clothes, give white vinegar a chance to work it's magic.
The Hotpoint experts say: "Just mix equal parts water and white vinegar, and apply it directly to the stain for 30 minutes before washing.".
Not only will your clothes come out sans-stink, they'll also get the added benefit of vinegar's fabric softening qualities.