AC (Alternating Current) - Alternating current, is an electric current which periodically reverses direction, whereas direct current (DC, also dc) flows only in one direction.

CC (Constant-Current Welding Machine) - These welding machines have limited short circuit current. They have a negative volt-amp curve and are often referred to as “droppers”. The voltage will change with different arc lengths while only slightly varying the amperage, thus the name constant current or variable voltage; used in Stick and TIG welders.

CV (Constant-Voltage, Constant-Potential (CP) Welding Machine) - Constant voltage speaker system, a distributed speaker system.“Potential” and “Voltage” are basically the same. This type of welding machine output maintains a relatively stable, consistent voltage regardless of the amperage output. It results in a relatively flat volt-amp curve (used in MIG and flux cored welders) as opposed to the drooping volt amp curve of a typical Stick (SMAW) welder.

DC (Direct Current) - DC is the unidirectional flow of electric charge. DC is the unidirectional flow or movement of electric charge carriers (which are usually electrons).

Duty cycle - The duty cycle of a welder is the amount of time the welder is designed to operate in a ten minute period, i.e., 20% = two minutes. Duty cycle can be increased on some models up to 100% with decreased output. However, duty cycle is rarely an issue for customers.

Filler metal - A filler metal is a metal added in the making of a joint through welding, brazing, or soldering.

Flux - Flux is a material included in a welding stick or fluxcored wire that gives off a gas when it burns. This gas serves to shield the welding arc. See shielding.

Shielding - The electric arc of a welder needs to be protected from the gases of the atmosphere in order to make a good weld. The gas either comes from burning flux (see flux) or from shielding gas (see shielding gas).

Shielding gas - Shielding gas is supplied directly from a gas cylinder and is required for wire welding with solid wire. The shielding gas is a mix of 75% Argon and 25% CO2 (C-25), 100% straight Argon for aluminum, and a mixture of Argon, CO2, and helium for stainless steel (also called "tri-mix"). These gases come in various cylinder sizes. See the Thoroughbred Industrial Cylinder Exchange section for specifics.

Stick - A stick is a metal electrode that also serves as the filler metal in the HF Welding process. The shielding gas is obtained from flux in the electrode outer coating. See flux.