Steel is basically Iron and Carbon with small amounts of other stuff like manganese. Low Carbon Steel only has .3 percent carbon. By comparison, cast iron has a full 3% or more. That’s why cast iron is more difficult to weld while carbon steel is the easiest metal to weld.
Tig welding is used extensively for pipe welding, aerospace, aviation, biomedical implants, fabrication of race cars, choppers, etc. It is much more precise and cleaner than mig welding or stick welding and definitely the coolest. Carbon steel and other metals as thin as razor blades can be welded. Outdoor windy conditions matter a lot and portable wind shields are a must if welding outside. Most tig welding is done in shops and indoors. It is one of the most versatile types of welding there is because virtually any type of metal can be welded with a few exceptions like certain alloys of aluminum that are considered unweldable such as 7075 aluminum.