can this gas be harmful?
Yes Inhaling it can be dangerous if done to excess, since helium is a simple asphyxiant and so displaces oxygen needed for normal respiration.
Helium
Inhaling helium can be dangerous if done to excess, since helium is a simple asphyxiant and so displaces oxygen needed for normal respiration. 
what is the meaning of metals and nonmetals in science It is a chemical element that mostly lacks the characteristics of a metal can you name some of its properties? Physically, they largely exist as diatomic or monatomic gases, with the remainder having more substantial (open-packed) forms, unlike metals, which are nearly all solid and close-packed. which are some of its categories? They can be divided into the two categories of "reactive nonmetal," and "noble gas. can you name some gases that fall under the second one? Helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn) when was the first gas mentioned discovered? In 1868 during a solar eclipse and who was the first to discover it? Georges Rayet what are some of the uses of this gas? It was primarily used as a lifting gas in lighter-than-air craft. During World War II, the demand increased for helium for lifting gas and for shielded arc welding. The helium mass spectrometer was also vital in the atomic bomb Manhattan Project. does it also have any medical uses? Yes it was approved for medical use in the United States in April 2020 for humans and animals.
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Helium [SEP] Hazards
Inhaling helium can be dangerous if done to excess, since helium is a simple asphyxiant and so displaces oxygen needed for normal respiration. Fatalities have been recorded, including a youth who suffocated in Vancouver in 2003 and two adults who suffocated in South Florida in 2006. In 1998, an Australian girl from Victoria fell unconscious and temporarily turned blue after inhaling the entire contents of a party balloon. Inhaling helium directly from pressurized cylinders or even balloon filling valves is extremely dangerous, as high flow rate and pressure can result in barotrauma, fatally rupturing lung tissue. Death caused by helium is rare.