Welding 101: What Welding Is, Its History, and How to Start

The U.S. Bureau of Labor Statistics projects roughly 47,700 welding jobs a year through 2032, even as manufacturers report a persistent shortage of qualified hands. Welding holds a bridge deck together, seams a pipeline, frames a car chassis, and joins the handle on a stainless pan. Almost nothing in industrial life skips it.

The practical tension for a beginner is choice: four common processes, a dozen certification paths, and a wide gap between entry-level pay and journeyman rates depending on process and industry.

Understanding what welding actually does to metal, how it evolved from forge to arc, and which process suits a first year of learning shapes every decision that follows, including how much a beginner setup costs and what a welder career pays.

What Is Welding? The Science of Joining Metal

Welding fuses two pieces of metal into one continuous piece by heating their edges past the melting point (roughly 2,500°F for mild steel) and letting the molten pools flow together. In most processes, a consumable filler metal is added to the joint to build up material and bridge the gap. Once the puddle cools, the result is a single solid section of metal, not two parts held together by an adhesive or fastener.

The Molecular Bond

Think of welding as gluing with molten metal, except the finished bond is typically stronger than the base metal itself. That is because there is no glue layer. When the edges melt and mix, the atoms of both pieces intermingle and share electrons in a continuous metallic lattice. The joint becomes chemically and structurally indistinguishable from the parent material, which is why a properly executed weld will often fail somewhere other than the weld itself under load.

Common Heat Sources

Different types of welding use different ways to generate the heat needed to melt steel, aluminum, or other metals:

• Electric arc: an electrical discharge between an electrode and the workpiece, used in SMAW, MIG, TIG, and FCAW. This is the dominant category in modern shops.
• Gas flame: a burning mixture of oxygen and acetylene, used in oxy-fuel welding and cutting.
• Laser and electron beam: highly focused energy for precision automotive and aerospace work.
• Friction: mechanical rubbing that generates heat without melting, used in friction stir welding of aluminum.

Filler Metal and Shielding

Molten steel is chemically hungry. If the puddle is exposed to oxygen and nitrogen in the surrounding air, it absorbs them and forms porosity, brittleness, and cracks. Every arc welding process therefore includes a shield: either a flux coating that burns off to create a protective gas cloud (as in stick and flux cored arc welding) or a bottled shielding gas like argon or CO2 blown over the puddle (as in MIG and TIG). The shield is not optional. It is what separates a sound weld from a decorative-looking failure.

A Brief History of Welding: From Forge to Arc

Forge Welding: The First 5,000 Years

The history of welding did not start with electricity. It started with a hammer. Forge welding, the oldest known joining method, dates back roughly to 3000 B.C.E., when smiths heated iron or steel until it turned plastic (soft but not liquid) and then pounded two pieces together until they fused.¹ No filler metal, no electrical power, just heat and pressure, often repeated over several reheats.

Blacksmiths used forge welding to build tools, weapons, chain, and architectural hardware, and it remained the principal way to join iron and steel right up to the late 19th century.

The Industrial Revolution Kept Swinging the Hammer

Through the Industrial Revolution (conventionally dated 1750 to 1850), the main process for joining wrought iron was still forge or hammer welding done in a blacksmith shop. Another early approach placed two iron pieces close together and poured molten metal into the gap so the joint filled and solidified as one.

For the big structures of the era, boilers, bridges, ships, and heavy machinery, builders largely relied on riveting and bolting rather than welding. Reliable fusion welding simply did not exist yet.

The Arc Arrives

In 1800, Sir Humphry Davy demonstrated an electric arc between carbon electrodes powered by a battery. He did not invent welding, but he proved an arc could produce extreme, controllable heat.¹ Vasily Petrov demonstrated a continuous arc in 1802.¹ Decades passed before anyone put that heat to work on a joint.

Key milestones that followed:

• Early 1860s: Henry Wilde used an arc to melt small pieces of iron together, and in 1865 received a patent described as the first tied to electric arc welding.¹
• 1881: Auguste de Meritens patented a carbon-arc method, used to weld lead components in lead-acid batteries. The same year, Nikolay Benardos demonstrated carbon-electrode arc welding in Paris, work generally credited as the first practical arc welding.¹ Patents with Stanislaw Olszewski followed between 1885 and 1887, with dates varying by country.
• 1886: Elihu Thomson developed resistance welding, which generates heat at the interface by passing current through clamped workpieces.
• 1890: C. L. Coffin patented arc welding with a bare metal electrode that melted and supplied filler metal itself.¹

From Bare Wire to Modern Stick

Coffin's consumable electrode set the stage, but bare wire produced weak, contaminated welds. In the early 1900s Oscar Kjellberg in Sweden and Arthur Percy Strohmenger in Britain developed covered electrodes whose flux coating generated shielding gas and slag.⁵ That advance turned the bare-wire idea into shielded metal arc welding, the process known as Stick Welding, and opened the door to the gas-shielded processes of the 20th century.

The Four Most Common Welding Processes: SMAW, MIG, FCAW, TIG

What's the actual difference between stick, MIG, flux-core, and TIG welding, and which one will you actually use on the job? These four processes cover the vast majority of shop and field work in North America. Each has a specific niche defined by portability, speed, precision, and the metals it handles best.

SMAW (Stick)

Shielded Metal Arc Welding, better known as stick welding, uses a consumable electrode coated in flux. When you strike an arc, the flux burns off and creates a gas shield that protects the weld pool from atmospheric contamination, while the metal core melts into the joint. Stick is the workhorse of construction, pipeline, structural steel, and repair work. It tolerates dirty or rusty metal, runs off a simple power source, and performs well outdoors where wind would blow away shielding gas. The tradeoff: slag cleanup between passes and a steeper learning curve for maintaining a steady arc length.

GMAW (MIG)

Gas Metal Arc Welding, commonly called MIG, feeds a continuous solid wire electrode through a handheld gun while an external tank supplies shielding gas (usually a CO2 or argon blend). Pull the trigger and weld: no stopping to change rods, no slag to chip. This is the process most instructors put in a beginner's hands first because the mechanics are forgiving and the results look clean quickly. MIG Welding dominates auto body shops, light fabrication, and manufacturing lines. Its main limitation is wind sensitivity, which makes it awkward for outdoor field work.

FCAW (Flux-Cored)

Flux-Cored Arc Welding looks and feels almost identical to MIG, using the same wire feeder and gun. The difference is inside the wire: a hollow tube packed with flux that generates its own shielding as it burns. Self-shielded FCAW needs no gas bottle, which makes it ideal for windy jobsites, ironwork, and outdoor structural welding. It deposits metal fast and penetrates thick material well. Expect more smoke and slag than MIG.

GTAW (TIG)

Gas Tungsten Arc Welding uses a non-consumable tungsten electrode to create the arc, while your other hand feeds a separate filler rod into the puddle. TIG Welding is the precision process: slow, clean, and capable of welding stainless steel, aluminum, titanium, and thin-gauge material where appearance and integrity both matter. Aerospace, food-grade piping, and custom fabrication rely on it. It also demands the most coordination of any process.

Each of these has a dedicated deep-dive page within Welding Processes covering equipment, technique, and certification paths.

Related Articles

Welding Process Comparison: Which Should You Learn First?

If you are new to welding, MIG (GMAW) on clean steel is the most forgiving starting point because the trigger-fed wire, smooth arc, and minimal spatter shorten the time from first bead to usable weld. Stick welding is cheaper to start but harder to master, and flux-cored is a budget-friendly alternative to MIG when a shielding gas tank is not practical. TIG offers the most precision for thin metals and alloys but has the steepest learning curve, so a practical path is to begin with MIG, build confidence with stick, and move to TIG when you want finer control.

Welding Joints, Positions, and Basic Terminology

Two welders can run identical machines on identical steel and get different results, because one is welding flat on a bench and the other is reaching overhead under a truck frame. Joint geometry and body position shape almost everything about how a weld behaves, so learning the vocabulary early saves confusion later.

The Four Main Joint Types

• Butt joint: Two pieces meet edge to edge, usually with their surfaces in the same plane. This is the classic pipe-to-pipe or plate-to-plate connection, and it is normally filled with a groove weld. Edges may be left square or beveled to open up room for filler metal.
• Lap joint: One piece overlaps another, like sheet metal panels on a vehicle body. The weld is typically a fillet run along the exposed edge of the top piece, sometimes on both sides.
• T-joint: The edge or end of one member meets the face of another at roughly 90 degrees, common in frames, brackets, and structural steel. A fillet weld in the inside corner is standard, though a groove weld is used when deeper penetration is required.
• Corner joint: Two pieces meet at an L, as on box frames and enclosures. Depending on whether the configuration is open, closed, or half-open, it may take a fillet, a square-groove, or a V-groove weld.

Positions and Why Flat Is Easiest

The American Welding Society labels positions with numbers: flat is 1G for grooves and 1F for fillets, horizontal is 2G and 2F, vertical is 3G and 3F, and overhead is 4G and 4F, the overhead groove position tested in 4G SMAW Certification. Flat is easiest because gravity pulls the molten pool down into the joint. Vertical work fights that pull, and overhead work has gravity dragging metal away from the joint entirely.

Terms You Will Hear Constantly

A weld bead is the strip of deposited metal laid down in one pass; bigger joints need several overlapping beads. Penetration describes how far weld metal extends into the joint from the weld face. The root is the innermost zone where the members come closest together, the starting point for root pass welding. Toes are the points where the weld face meets the base metal, and reinforcement is the crown sitting above the base surface, where Cap Welding Techniques shape the final bead.³

From Setup to First Weld: A Beginner's Roadmap

The path from first interest to first weld is simpler when you follow a set order. Use this beginner roadmap to build good habits before you strike an arc.

Welding Safety: PPE, Ventilation, and Electrical Basics

What gear do you actually need before striking your first arc? The honest answer is more than a helmet, and none of it is optional.

Personal Protective Equipment

OSHA's general PPE rule, 29 CFR 1910.132, applies to welding along with the process-specific requirements in 1910.252 through .254.² At minimum, expect to wear:

• Auto-darkening helmet: Shade needs vary by process and amperage. Stick welding (SMAW) typically calls for shade 7 to 11, MIG Welding and flux-cored (FCAW) run 7 to 10, and TIG usually sits at 8 to 10. There's no single "correct" shade for all electric welding, so check the chart for your process and current first.¹
• Fire-resistant jacket or sleeves: Clean, dry cotton or FR fabric, never synthetics that can melt onto skin.
• Leather gloves: Dry, hole-free, insulated, with long cuffs to protect wrists from spatter and UV.
• Steel-toe boots: Leather uppers, no exposed laces or mesh that sparks can catch.

Fumes and Ventilation

Welding fumes are a mix of metal oxides, and some base metals or coatings add real chemical risk. Stainless and other chromium-bearing alloys can generate hexavalent chromium, regulated separately under 1910.1026, while certain coatings raise cadmium (1910.1027) or lead (1910.1025) concerns.²

OSHA's ventilation rule, 1910.252(c)(1), requires adequate ventilation for every welding or cutting operation. As a rule of thumb, mechanical ventilation becomes necessary when a welder has less than 10,000 cubic feet of space, works under a ceiling lower than 16 feet, or is in a room smaller than 22,500 cubic feet per welder.² When local exhaust or general ventilation can't keep concentrations down, especially in confined spaces governed by 1910.146, move to an airline respirator under 1910.252(c)(4) and 1910.134 rather than relying on a disposable dust mask.³ Also steer clear of chlorinated solvent vapors near the arc: UV light can break them down into phosgene, a hazard specifically flagged in 1910.252(c)(3).²

Electrical Safety

Arc welding equipment falls under 1910.254, which covers grounding, cable condition, and holder insulation.⁴ Practical habits that follow from it: keep gloves and boots dry, never weld standing in water or on wet ground, inspect cables and holders for cracked insulation before each use, and disconnect power before servicing a machine, applying lockout/tagout under 1910.147.⁵ Never use structural steel, pipe, or hoist chains as a ground path.

Why It's Non-Negotiable

The ANSI/ASSP Z49.1 standard, "Safety in Welding, Cutting, and Allied Processes," works alongside these OSHA rules as the trade's core safety reference.⁵ For a beginner, skipping any of this isn't a shortcut. It's how welders get burned, gassed, or shocked in their first month , basic Welder Safety isn't optional.

Beginner Welding Setup Costs: What to Expect

A capable beginner welding setup in 2026 runs anywhere from about $300 to $3,300, depending mostly on process and whether you buy shielding gas.¹ Stick is the cheapest way in, MIG Welding sits in the middle, and TIG Welding costs the most because the machines are more sophisticated and the accessories add up quickly.

Machine Prices by Process

Entry-level hobbyist machines cluster in predictable bands:

• Stick (SMAW): $150 to $250 for a basic inverter, $250 to $400 for a solid mid-range unit², $400 to $700 for something more capable³.
• MIG (GMAW/FCAW): $200 to $300 at the bottom, $400 to $700 mid-range², $900 to $1,200 for gas-capable machines with better duty cycles⁴.
• TIG (GTAW): $350 to $500 entry³, $500 to $1,000 mid-range, $1,200 to $2,000 for AC/DC units that can weld aluminum⁶.

Watch what is actually in the box. Cheaper TIG machines often exclude the torch, regulator, foot pedal, or gas hose, and higher-end welders sometimes ship without leads and clamps.

Safety Gear and Accessories

Regardless of process, budget for the same core kit:

• Auto-darkening helmet: $50 to $200 for a usable model⁷, $80 to $250 for a shade 9 to 13 variable lens⁸, up to $400 for premium optics⁹.
• Gloves: $15 to $35 for MIG/stick⁷, $20 to $40 for thinner TIG gloves⁸.
• Fire-resistant jacket: $40 to $150⁸.
• Angle grinder, wire brush, clamps, safety glasses, steel-toed boots: plan on another $100 to $200 if you are starting from zero.

Gas and Consumables

Stick and self-shielded flux-core skip the cylinder, which is a real savings. Gas MIG and TIG do not. A cylinder deposit or purchase runs $60 to $350 depending on ownership vs lease⁷⁹, a 125 cu ft argon rental averages $150 to $300 per year⁸, and an 80 cu ft 75/25 refill is $35 to $55⁷. Flux-core wire runs $10 to $20 per pound¹⁰, tungsten electrodes $10 to $30 per pack⁶.

Ballpark Totals and Used Gear

Realistic all-in starter budgets: stick $300 to $1,800, MIG $350 to $2,400, TIG $650 to $3,300¹. Used machines can cut those numbers substantially, but inspect leads, wire drive rollers, and the transformer or inverter board carefully before you hand over cash.

Welding as a Career: Jobs, Skills, and Salary Outlook

Welding careers include hands-on roles such as welders, cutters, and brazers who join metal components using arc or gas processes, as well as machine setters and operators who tend automated or semi-automated welding equipment. Day-to-day work often involves reading blueprints, preparing joints, selecting filler metals, setting machine parameters, and checking weld quality; common skills include blueprint reading, basic math, manual dexterity, and attention to safety. Pay varies significantly by industry, location, certifications, and experience, and the national estimates below from the U.S. Bureau of Labor Statistics show median, percentile, and total employment figures for three related welding occupations.

Frequently Asked Questions About Welding

Welding can feel like a dense topic at first, but a few core questions cover most of what beginners need to know. These answers summarize the processes, history, and entry path into the trade.

What is arc welding?

Arc welding is a family of processes that joins metal by melting the workpieces with heat from an electric arc. The arc is a controlled discharge through ionized gas, or plasma, between an electrode and the workpiece. It may or may not use filler metal, and some processes may also apply pressure.

When was stick welding invented?

Stick welding, formally Shielded Metal Arc Welding (SMAW), is generally dated to 1890, when Charles L. Coffin patented an electrode melting and joining process. Earlier carbon arc welding appeared around 1881 to 1882 by Nikolai Bernados and Stanislaw Olszewski, but modern flux-coated SMAW came later.

Which welding process is easiest for a beginner to learn?

For most beginners, MIG welding, Gas Metal Arc Welding (GMAW), is the easiest to learn, especially indoors on clean mild steel. A continuously fed wire reduces stops and makes starting simple. The easiest process can vary by material, environment, equipment, and instructor. Flux-cored is often beginner-friendly outdoors or on thicker steel.

What are the 4 main types of welding?

The four most common types are MIG, TIG, stick, and flux-cored. MIG (GMAW) feeds a wire with shielding gas. TIG welding (GTAW) uses a nonconsumable tungsten electrode and separate filler. Stick (SMAW) uses a flux-coated consumable electrode. Flux-cored arc welding (FCAW) uses a tubular wire with flux inside.

Do I need a college degree to become a welder?

No. Welders normally enter the field with a high school diploma or equivalent and moderate-term on-the-job training. The AWS Certified Welder credential has no formal education or experience prerequisites; you qualify by passing a performance test. Common routes include vocational school, a community-college welding certificate, apprenticeship, employer training, or military training.