Asbestos is a natural rock.
When crushed it turns into small fibres that look like needles of glass under a microscope.
Asbestos was used for many purposes until recently. Its properties mean it is a very good insulation of heat and electricity, can be turned into useful roofing tiles, flooring tiles, and added to plaster in textured ceilings such as Artex decorative coating.
However, we now know asbestos is dangerous and the needle like fibres cause terrible illnesses when asbestos containing materials are damaged, the fibres can release and are easily inhaled. In the UK asbestos is no longer used, but many millions of buildings still have asbestos in them.
There are 3 main types of asbestos, white, brown and blue. White is not too bad, but brown and blue are very dangerous.
The type of asbestos most commonly found in UK homes is white.