It depends on the type of steel. All steel has additives called Alloys. Stainless Steel, for example, has Chromium and Nickel added to already Alloyed Steel. High Yield Steel would have more alloys than Mild Steel. In some situations you would have to know the Alloys and amounts of each to determine what Electrode is required. Using the wrong Electrode can cause a weld to fail.
FYI an Alloy is an Element added to another Element to change its characteristics.
There are far more than 5 types or processes of welding. Currently the American Welding Society (AWS) states that there are more than 80 different welding and joining processes. However, some of the common welding processes include shielded metal arc welding (SMAW), gas metal arc welding (GMAW), gas tungsten arc welding (GTAW), flux cored arc welding (FCAW), and oxyfuel gas welding (OFW).
EFW: Electric Fusion Welding is a more general term which includes Electric resistance welding (ERW) and other types of welding such as Arc welding.
In Pressure Welding the parts(work pieces) to be joined are heated only up to the plastic state and then fusedtogether by applying the external pressure.the two different types of pressure welding are:forge welding and resistance welding
Gas, arc, mig and tig.
there are one types of weilding is weilding.
Read here under this section, very informative: http://en.wikipedia.org/wiki/Welding#Processes
It is a good idea to purchase and utlize a welding fume extractor. There are different types of welding fume extractors and brands available for purchase.
Branson Ultrasonic offer welding technologies. For example, they offer Linear Vibration Welding, Orbital Vibration Welding, as well as many other types of welding tehcnologies.
it is not a question of which is better. the welding types are chosen according to our own requirements
Thorium welding rods offer several advantages over other types of welding rods. They provide better arc stability, higher current-carrying capacity, and improved heat resistance. Additionally, thorium rods have a longer lifespan and produce less spatter during welding, resulting in a cleaner and more efficient welding process.
Types are aluminium, steel, bronze, brass, etc...
2 basic types, Gas shielding, and flux shielding. Gas shielding comes from compressed tanks of inert gas such as argon. these gases are pumped through the welding hose and over the weld pool. The flux type protects the weld by covering it in a layer of slag that prevent it from being contaminated by the surrounding air.