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; on the client device, 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, wherein the data structure is independent of the browser-based application and is received from the server in a data file separate from the browser-based application; and by the browser-based application 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.