Judgment seat of Christ. The greek words is "bema" which means a "step or raised place". This was commonly used by the greeks to "reward" Ath;lets for their work in the olympic games.
Paul tells us in 2 cor 5 that we (Christians) will all appear in front of this "judgment seat" and be rewarded for what we did on earth, good or bad. Salvation is not in issue at this judgment. Only rewards (think Gold silver precious stones, wood hay straw) where the good we did we are rewarded with these things of value, the bad we have done are burnt up, and no reward is given.
The great white throne judgment, however, is a different judgment. Different people will be here.
1. Death and hades, Those dead to Christ at the end, and those in hades awaiting their final judgment.
2. The reward, All will be sent to eternal darkness, called the second death.
No christian will be at this judgment, this is for the damned. Where they are given an opportunity to appeal Gods decision (judged according to the ir works) and found guilty, because they were not written in the book of life.