How many pictures can a 2 GB memory card hold?

it depends on what size the photos are. If you have a maybe 5 gb or 8gb camera you wont fit a lot on a 2Gb memory card. It varies from about 40 to several thousand, depending on file type, resolution and compression. Top end JPEGS on a 6 MB camera would fit about 600 on a 2 GB card. Cameras are rated in megapixels, not gb as above; certainly most cameras these days are in the range of 5 megapixels to 12 megapixels.