This is an important one, purchased through CRKN. It joins Google Scholar and Web of Science as general indexes that
employ citation tracking as sorting and searching strategies.
Try out some comparative searches, I found that all three products returned different results. I have to say I prefer the SCOPUS
interface, but others may prefer whats familiar. Still, even if you start with one, you may well find yourself using the others.
I've done a bit of reading and here are some key differences
Web of Science--goes back further, covers some humanities material
SCOPUS--strong for STM, includes books and conference proceedings in these areas
Google Scholar--quick start, uncovers the unexpected