Drip irrigation was chosen because it is the most effective way to get moisture to the plant roots. When water is dripped onto one spot, it spreads underground in a shape like an inverted ice cream cone, just about the same way plant roots themselves naturally grow. So it makes sense to have a drip emitter at each plant. Drip irrigation saves about 95% of the water used by overhead sprinklers.
Laying out the dripline
The "end of the line" is the most important part of drip irrigation. The idea we came up with was to have the irrigation lines in place before the first plantings. That way the plantings could be spaced out just right and the plants themselves would not be under any water stress when they were first starting out.
We use several kinds of 1/4" drip line: normal straight line, porous line, line with emitters embedded every 6", 9" or 1'.