Push-fit fittings (SharkBite is the most common brand) snap onto pipe with no tools, no heat, and no special skills. Push the pipe in, the internal teeth grip it, the O-ring seals it. Done. They work on copper, PEX, and CPVC in any combination -- which makes them perfect for repairs where you are joining different pipe types. More expensive per fitting than soldering or crimping, but the time and tool savings are massive. Ideal for emergency repairs, tight spaces, and DIYers who do not want to solder.