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+# FIR vs IIR
+FIR Filters are always stable as they can be implemented without feedback loops, the integration
+of which in IIR filters can lead to the eponymous infinite responses.
+IIR filters however can implement similar sharpness or selectivity to FIR filters with significantly
+lower order filters, resulting in lower computation cost.
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+# Bits, Symbols, Alphabet
+In terms of raster images,
+- bits are still bits (0/1)
+- symbols are single pixels made up of rgb values
+- the alphabet is the set of all possible rgb values