Wikipedia has a good entry on Linnaean taxonomy. This is important to me as I am trying to classify and identify the insects and flowers I photograph.
Of note is that the scheme for naming a genus and species pair calls for a capitalized genus name and a lowercase species name (e.g. Viola sororia, the common blue violet). Another thing to note, especially with insects that can have many species for a genus, is that it's acceptable to give the genus name followed by "sp.", indicating that it's an unclassified species for that genus (e.g. Phidippus sp.).