PART I: BASIC INFO -
There are two types of graphic files: Vector and Raster. Vector graphics describe shapes mathematically, whereas Raster, or bitmap, files describe shapes as a pattern of dots or pixels.
Vector images consist of drawing objects, such as lines, circles, and squares. Vector images can also contain text with font information that, unlike raster text, can be changed . Vector images are usually created by CAD, drawing, charting, or graphing software applications, (such as Corel Draw).
Raster images consist of thousands of dots, called pixels, that are arranged in a rectangle called a bitmap. Raster images are usually created by scanners or paint software applications, (such as Paint Shop Pro). All fax formats are raster.
This is partly why, when using Raster graphics in PA such as PCX's or TIFF's, you can only rotate rasters in 90 degree increments,and why they do not necessarily stretch very well to larger sizes.

There is a third graphics format type which are Metafiles. These can contain both raster and vector components.
In general, you can convert from and to the following:
a VECTOR file format to a VECTOR file format
a VECTOR file format to a RASTER file format
a RASTER file format to a RASTER file format

GIF's and PRINT ARTIST:
Unfortunately, gif's are a raster format, as are all bitmap graphics. So you will always have the background. The graphics that do not show a background are vector format. Gif's have the capability of making the background transparent but you can not use gif's in the current versions of PA. The earlier version PA 2.5 did accept gif's.

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PART II - MORE TECHNICAL INFO -
Vector files rely on a language (for example, PostScript) to describe how to draw a graphic. It's very simple to convert vector graphics into raster graphics - simply process the vector information as if you were going to print and save the output as a raster graphic. As a result, vector files aren't tied to a particular resolution - you can generate raster images of any size from vector files.
Unfortunately, converting a raster graphic into a vector graphic isn't as easy. To do so, the computer has to interpret the patterns of pixels in the raster image as shapes and then figure out how to write the directions to draw them. Some tracing programs can convert raster graphics to vector graphics, but the results are less than perfect.
To make things more confusing, you can embed a raster graphic in a vector graphic, but never vice versa. Because a vector graphic is a description of how to draw an image, you can embed a raster graphic by including the raster information in the vector graphic. Basically, you create a shape and give it a complicated fill - the raster graphic. For example, saving a Photoshop file as an EPS embeds a raster graphic inside a vector graphic.
However, you can never embed a vector graphic in a raster graphic because a raster graphic can't contain vector information. The only way you can combine a vector graphic with a raster graphic is to convert the vector image to raster information first and then consolidate the two.

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PART III: VECTOR GRAPHICS - in alphabetical order

• A1 Encapsulated PostScript (dest. only)
• CGM Compuler Graphics MetaFile
• DRW Micrografx Draw
• DXF AutoCAD
• EPS Encapsulated PostScript (dest. only)
• GCA IBM GOCA
• GEM GEM Metafile
• IGF Inset Systems IGF
• MCS MathCAD (dest. only)
• MET PM Metafile (dest. only)
• PCT1 Macintosh PICT (sourcc only)
• PCT2 Macintosh PlOr
• PIC Lotus
• PIX Inset Systems PIX
• PGL HP 7475A Plotter
• P10 Tektronix Plot 10 (Source only)
• TXT ASCII Text
• WMF Windows Metafile
• WPG WordPcrfect Graphic

PART IV: RASTER GRAPHICS - in alphabetical order

• ATT AT&T Group 4
• BMP Windows/ OS/2 Bitmap
• CAL CALS Raster
• CPR Knowledge Access (source only)
• CUT Dr. Halo
• DBX DataBeam
• DIB Windows/ OS/2 Bitmap
• ED5 EDMICS
• EPS Encapsulated PostScript(dest. only)
• GED Wicat
• GIF CompuServe
• ICA IBM IOCA
• ICO Windows Icon
• IFF Amiga ILBM
• IGF Inset Systems IGF
• IMG GEM Painl
• JPG JPEG
• KFX Kofax Group 4
• MAC MacPaint
• MSP Microsoft Paint
• PCD Photo CD
• PCL4 HP LaserJet II
• PCX PC Paintbrush
• PCT1 Macintosh PICT (source only)
• PCT2 Macintosh PICT
• PIX Inset Systems PIX
• RAS Sun Raster
• SBP IBM Storyboard PIC (source only)
• TGA Truevision
• TIF TIFF
• WPG WordPerfect Graphic