Single item page - a.k.a. detail page.
If there is only one item on a page, such as a product, a person or an address, we call this a single item page.
If the data you want is on a single item page, you more than likely want to get corresponding data from lots of similar single item pages and you can easily do this by adding URLs to your Extractor after you have created it.
Examples of single item pages: Drums
For single item pages, each URL will return one row of data.
Multiple item page - a.k.a. list page
If there are multiple items on a page, such as a list of products, a table of data, or a page of links, we call this a multiple item page.
If the data you want is on a multiple item page, you may be doing this to extract links to use as URLs in a single item page Extractor, or you may be simply extracting a table of data. If the data exists across more than one page it is easy to add URLs to your Extractor
after you have created it.
Examples of Multiple item pages: Products
For multiple item pages, each URL will result in many rows of data.