im trying to upload pictures onto my mac using a memory card, but im not sure if the slot on the left hand side is the right one. it looks kind of big. does anyone know if its the right one??
Go to your nearest electronics/computer dealer store. Purchase a USB-SD interface device (assuming your memory card is indeed SD type). Put the SD card in the new device, plug the new device into USB slot of your Mac.
The ExpressCard slot isn't meant for memory cards such as yours. Don't worry about what it *is* meant for, in all probability, you'll never find a use for it.
ExpressCard is analogous to expansion slots in a desktop computer. It has two connections inside, a single PCIexpress lane and support for USB 2.0. You can get wireless modems, solid-state hard drives, even a memory card reader which might suit you better than an external USB card reader.