By material
1.Steel cylinder,made of seamless steel pipe usually for industrial use
2.Aluminum cylinder made of aluminum ,usually for medical O2 or CO2
By manufacturing industrial gas cylinder have 3 types
1.Type1 steel cylinder made of seamless steel pipe or billet,usually 100-200bar
2.Type2 steel liner wrapped by glass fiber ,can hold more pressure 250bar
3.Type3 aluminum liner by carbon fiber wrapped ,pressure can reach more higher 300bar even 500-700bar