What is a good overview book on investment management?

I'm starting an internship very soon at an investment management company, and I could use a refresher, to say the least. I'm looking for a concise book that explains the basics of investing (stocks, bonds, mutual funds, options, etc) so I don't sound like an idiot when I show up to work. Preferably a book available in ebook form. I suppose a sufficiently detailed web article would work as well. Thanks, from my boss as well haha.