What is the "inhalable particulate matter" mentioned in the weather forecast?

In other words, the primary pollutant now is inhalable particulate matter. Its explanation is that

Total suspended particulate matter refers to the general name of solid and liquid particulate matter floating in the air, and its particle size range is about 0. 1- 100 micron. Some particles, such as smoke and dust, are visible to the naked eye because of their large particle size or dark color. Others are small enough to be observed with an electron microscope. Generally, the particle size below 10 micron is called PM 10, also known as inhalable particles or floating dust. The smaller the particle size, the deeper it enters the respiratory tract. Particles with a diameter of 10 micron are usually deposited in the upper respiratory tract, those with a diameter of 5 microns can enter the deep respiratory tract, and those with a diameter less than 2 microns can 100% penetrate into bronchioles and alveoli. Inhalable particulate matter (PM 10) lasts for a long time in the ambient air, which has a great impact on human health and atmospheric visibility. Some particulate matter comes from direct emissions from pollution sources, such as chimneys and vehicles. Others are fine particles formed by the interaction of sulfur oxides, nitrogen oxides, volatile organic compounds and other compounds in the ambient air, and their chemical and physical compositions vary greatly due to different places, climates and seasons. Inhalable particles usually come from motor vehicles running on unpaved asphalt and cement roads, the crushing and grinding process of materials and the dust raised by the wind. Inhalable particles will accumulate in the respiratory system after being inhaled by people, causing many diseases. Contact with coarse particles will harm the respiratory system and induce asthma. Fine particles may lead to heart disease, lung disease, respiratory diseases and reduce lung function. Therefore, for sensitive people such as the elderly, children and people with heart and lung diseases, the risk is greater. In addition, the particulate matter in the ambient air is the main reason for reducing visibility and destroying the surface of buildings. The monitoring and analysis method of inhalable particulate matter is mass method.