Lossless compression (like JPEG) retains values and lowers file size. However, lossy compression (like LZ77) reduces file size by eliminating redundancy.
Bit depth is the amount of detail in each pixel expressed in units of bits. 1-bit rasters contain 2 values while 8-bit rasters range from 0-255
Deploying efficient raster GIS compression techniques means reducing storage space. It can save money, time and also help network performance.
Unsigned integer rasters are non-negative numbers. Signed integers can store negative values. IMG, TIFF & GRID formats are acceptable for signed integer