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Quite the opposite of Active-matrix.
Passive-matrix is an older LCD technology that controls and RGB of pixels using a matrix of TFTs and capacitors .
Unlike Active, however, which controls each individual pixel, Passive can only use one line of vertical or horizontal at the same time.
Also, because it requires a horizontal and vertical change for every pixel, it is significantly slower than an Active-Matrix display.
Any fast movement on a passive-matrix display will be hurt by "ghosting," the effect of blurry or faded edges due to slow response time.
All new monitors, unless you are buying a very, very cheap model, will use passive-matrix.