[flash]

Hate to be technical, but the need for hot water depends! Depends on if you have soft water, what detergent you use, etc. If you are just washing dirt off, cold is okay, but if you want to get dirt or stains OUT, or trying to kill bacteria/dust mites/other live things, temperature does matter.

Laundry detergents (surfactants) are designed and tested to work best at specific temperatures. You need them to get in and do their job. Seriously, a fortune goes into designing and improving every year!

For towels, anything that may have mold, mildew, etc., hot is best. Bleach works for whites, but it also breaks down the fabric, so it wears out much faster. Allergists will insist you wash sheets HOT, but rinse in cold.

Baking soda OR vinegar both have cleaning properties, but if you use them together, they cancel each other out.

I wash most things warm, I rinse everything cold. But I adjust my detergent to what I'm trying to get out.