Parts books were often issued as microfiche, though this has fallen out of favour.
Now, many manufacturers offer this information digitally in an electronic parts catalogue.
This can be locally installed software, or a centrally hosted web application.
In the automotive industry, electronic parts catalogues are also able to access specific vehicle information, usually through an online look-up of the vehicle identification number.
This will identify specific models, allowing the user to correctly identify the required part and its relevant part number.