PDF (adobe.com)

Optimize GIF, PNG, TIFF, BMP, and PICT files

Each graphic file format in Fireworks has a set of optimization options. The 8-bit file types such as GIF, PNG 8, TIFF 8, BMP 8, and PICT 8 offer the greatest amount of optimization control.

For continuous-tone web graphics such as photos, use a 24-bit format such as JPEG. (See Optimize JPEGs.)

Fireworks optimization settings are similar for all 8-bit graphic file formats. For web file formats such as GIF and PNG, you can specify the amount of compression.

As you experiment with different optimization settings, use the 2-Up and 4-Up buttons to test and compare a graphic's appearance and estimated file size.