Vgs vs. Ids curve:
When fixing Vds of a transistor, Ids varies when Vgs changes, forming a “Vgs vs. Ids” curve.
This curve can be used for studying how the carriers (electrons or “electric holes”) in the channel are raised to the conducting zone. Both the critical voltage at which a channel is formed and the critical voltage of a linear zone can be measured, providing important curves for the study of transistor characteristics.