1. A method of spell checking a document, the method comprising: at a client device, activating a browser-based application received from a server through a network; receiving a data structure for a dictionary comprising a list of correctly spelled words from the server, the data structure utilized to prune the number of searches of the dictionary to match a word to strings associated with valid words in the dictionary; and at the client device, determining a word as having a correct spelling when the word matches a string associated with a valid word in the data structure for the dictionary.