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1 for $2.29
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10pcs for $19.95
This is an 8x8 LED matrix in red. We use this matrix for our Mini Scrolling LED Kit. The LED's are connected in a row cathode configuration, so you can turn on a row by pulling a single pin to ground (typically with an NPN transistor). All of the columns have a common anode. Yes, you're right, row/column/cathode/anode doesn't really matter because the matrix is square, but they're still manufactured with both pin configurations. The third image below shows this 20x20mm matrix sitting next to a 60x60mm matrix. These are high quality and will plug directly into a standard breadboard.
If you're not familiar with how displays work, you may be asking why there aren't enough pins to control each pixel individually. This would require a lot of pins and wires/pcb traces to make it work. The solution is to only light up one row at a time so that each one is on for 1/8 of the time. Do this very fast (>60Hz) and it will look good to the human eye. This is called multiplexing, and makes for a fantastic intermediate electronics project.