I thought it was just the QR and the Data Matrix 2d barcodes. These two types of code are shown in the icon for the barcode reader.
I just set my icons to animate on the phone and now I notice that the icon for the bar shows a QR barcode with a "normal" 1D barcode in front.
I cannot read anything other than the 2D ones, but I did read that someone once read a 1D barcode.
Can it or can't it read 1D codes?
Well I have partially answered my own question.
Using this site http://www.terryburton.co.uk/barcodewriter/generator/ I managed to get the N95 to "read" 3 different formats so far. EAN13, Interleaves 2 of 5 and ISBN.
Although it thinks it read the code, the actual numbers it displayed were not correct. Although the last 4 digits of the ISBN one I tried were correct once.
All barcodes have check digits so I don't know why the N95 bothers to display anything when it is clearly wrong.