/diy/ - Do It Yourself

A long time ago I was told capacitors will stop any current flowing through it, prevent it from discharging out the other side and absorb current until it's full. Once it's at full capacity it will release all of it's charge in one big surge. Then later I read in a different tutorial they absorb it when current is flowing then will slowly release it when current stops. I need this settled once and for all. Which is it? Or are both wrong? Do capacitors discharge in one big surge or slowly release over time? Does current need to stop before they will discharge? Will current continue to push through to the other side of the capacitor or does the capacitor stop it all together? How the fuck do they really work?