Galvanized steel
Grey, threaded at the joints, and magnetic. Common in homes built before the 1960s, so plenty of it survives in Floral Heights and the older parts of town.
The issue: it rusts from the inside. The bore narrows over decades until pressure drops, and rust colours the water. It has no remaining service life anywhere in Wichita Falls. Replacement, not repair.
Polybutylene
Grey, flexible plastic, often stamped PB2110, usually with plastic or crimped metal fittings. Used from the late 1970s into the mid 1990s.
The issue: a poor reliability record, and it tends to fail suddenly at the fittings rather than warning you first. If you have it, plan the replacement rather than waiting for the failure.
Copper
Reddish brown, rigid, soldered joints. The standard for decades and still a perfectly good material.
The issue: our hard water works on it from the inside over a long period, and under a slab it also takes soil movement from outside. Copper that has produced two slab leaks is usually telling you something.
PEX
Flexible plastic, commonly red and blue for hot and cold, with crimped or expansion fittings. Standard in newer construction and most repipes.
The issue: few, in practice. It tolerates freezing better than rigid pipe because it can expand slightly, which matters in North Texas. Keep it out of direct sunlight, which degrades it.
CPVC
Cream or tan rigid plastic with solvent welded joints. Seen in some builds from the 1980s onward.
The issue: it becomes brittle with age and can crack, particularly at joints and where it has been stressed. Not automatically a problem, but worth watching in an older installation.
A mixture of several
Extremely common in homes that have been added to or partially repaired over the years.
The issue: the system is only as reliable as its worst section, and dissimilar metals joined without the right fitting corrode at the connection. A mixed system is often the strongest argument for doing the whole house at once.