What matching system uses a short length of transmission line connected in parallel with the feed line at or near the feed point?
Why A stub match is a short piece of transmission line, usually shorted or open at its far end, connected in shunt (parallel) with the main feed line at or very near the feed point. A shorted or open line shorter than a quarter wave behaves as a pure reactance, so by choosing its length and position you can cancel the reactive part of the load and transform the remaining resistance to the line impedance. This is the classic single-stub tuner seen as a circle-to-circle move on the Smith chart.
Watch out The gamma and T-matches are different animals: they use conductive rods running alongside the driven element and tapping it at points away from center (the gamma is the single-sided version, the T is the symmetric balanced version), and the delta match fans the feed line out to two points on the element. None of those is a piece of transmission line in parallel with the feed line.
Stub = a stubby length of line hung in parallel; gamma/T/delta = rods tapping the driven element.