Many new symbols are available to you if you have the AMSFonts installed.
The amssymb style option gives you all the font capabilities of the
amsfonts style option and further defines the commands to get the
symbols shown in Appendix A. See Appendix A for examples of the symbols and
instructions on use. These characters will scale correctly in different
areas of the paper and in superscripts. Note that the symbols and typefaces
in Appendix A will not be printed unless you have the AMSFonts installed
and have selected either the amsfonts or amssymb style
option.