Not only this, but even the ideal temperature of the water is indicated via those tags. Hot, cold, or regular- which water temperature is suitable for which material is a key point. Another point to remember is the delicacy of the cloth you're washing. Some apparel has delicate details like tiny embroidery or sequins, so washing by hand is the best way to handle them.
All in all, the various symbols on the tiny tags inside your clothes point out to all these: ironing, dry cleaning, washing and more. These symbols have a basic layout for the category they stand for, and additional dots and lines added to each symbol give further guidance. To learn more what the various symbols mean and how to launder like a boss, check out the infographic below.

Infographic by: www.partselect.com