RoHS (Restriction of Hazardous Substances) is a European Union (EU) directive that restricts the use of certain hazardous substances in the manufacture of electrical and electronic equipment. RoHS compliance means that a product meets the requirements of the RoHS directive and does not contain more than the allowed levels of the restricted substances.
The RoHS directive applies to a wide range of products, including computers, appliances, lighting, and consumer electronics. It covers the following hazardous substances:
Lead (Pb)
Mercury (Hg)
Cadmium (Cd)
Hexavalent chromium (Cr VI)
Polybrominated biphenyls (PBB)
Polybrominated diphenyl ethers (PBDE)
RoHS compliance is important because the restricted substances can have negative impacts on human health and the environment. For example, lead can cause damage to the nervous system, while mercury can have toxic effects on the brain and kidneys. By restricting the use of these substances, the RoHS directive helps to reduce the potential negative impacts of electrical and electronic equipment on human health and the environment.
See here how manufacturers can manage compliance of RoHS.