Buffered output purpose?

[kvb]

I'm about to get into the mini and mosfet boosters so I wonder - What is the purpose of a buffered output?

I know about driving long cables - but that's what I thought boosters did.  Does the buffer allow the booster to drive another effect?

[davebungo]

Usually, a buffered output is provided in order to drive an unknown impedance e.g. a long cable to an amp or a low input impedance amp or effect or whatever.  Many effects provide buffering on the output for this purpose but it does not follow that a booster will or should provide such a facility.  A booster only has to provide voltage gain in order to be a called a booster.