the PS system has both, a high pressure line and a return line (low pressure)
the high pressure line uses metal flared fittings on both ends, from pump to box, this line holds like 1200# of pressure at times, but replacements are available at most auto parts stores for cheap.
the low pressure line is a trans fluid style hose held on with hose clamps, yes you can replace it with any power steering or trans cooler hose.