In an apparatus for storing articles, bins have a sensor for detecting the presence of an article in a bin and an optical code reader for reading a bar code on the article. The presence detector and the optical code reader are coupled to a circuit which provides an indication of the identity and location of a coded article. The apparatus is particularly well suited for use in the manufacture of semiconductor devices, when wafer cassette boxes are provided with a suitable bar code. Alternatively, the bins may be disposed upon a remotely guided vehicle, thereby making the apparatus useful in an automated manufacturing process.