I was a "welder" for several years about 20 years ago. As mentioned above, the term "welder" can be a pretty broad definition. I worked in shipyards where the "welders" did absolutely nothing but weld. There were others such as "shipfitters" (which is what I actually was) who did the actual construction. We would measure, layout, cut the steel and put it together. We would weld it enough to hold and then the "welder" would come in. Of course, when building a ship, the "small" welds that we would do to hold it, would be 10 to 12 inches long on 2 or three inch thick steel. I much more enjoyed the actual building of the items rather than simply pulling the trigger on a mig all day. I also worked in truck body and trailer fabrication, heavy equipment repair etc...
I actually come from a long line of "welders" or more properly "iron workers". My father was a boilermaker (fancy term for a steel fabricator/iron worker) in a mine. My mother's father was a structural iron worker that built dams, radio towers, titan missile sites (during the cold war) etc... As I grew up I learned the trade. When I got out the military, I had a job the next day. Welders/iron workers are always needed. I never had an issue finding a job. I always got paid well (I used to carry around two or three weekly paychecks until I got around to going to the bank) It is hard and dirty work. Jobs can last months or years. It stinks when your foreman comes in and hands you a "pink slip" and lets you know you have been laid off. Injuries are common (cuts, burns, back injuries etc..) Breathing in welding fumes all day for years will destroy your lungs (my Dad is a perfect example of that right now). It can be a very flexible, transient job. I used to work with a lot of guys that would go up and work in Alaska during the summer (canneries or the pipeline) and then come down and work short contracts in southern California in the winter. Even back then (again 20+ years ago), wages were 30 plus dollars an hour. Recently I spoke to some guys that were making $75.00 an hour (plus per diem) on a job. That job only lasted a few months while a company had to catch up on a job.
There are a lot of positives in being a welder/fabricator, but there are negatives also (as I mentioned above).
Working a trade such as a welder (or a carpenter, electrician, plumber etc...) is an honest, honorable career. I am the result of generations of blue collar tradesman that provided for their families. Skilled tradesman are harder and harder to find. I left the trade because I was tired of being laid off, plus I found a job that took be closer to my family. To this day, I keep a small welding machine in my garage and use it several times a month. It is a skill that I use all the time. Even if you don't want to do it as a career, it is a great skill to have and I encourage you to learn it you are interested in it.