Word Services is not just for spellchecking - server applications can do any sort of operation on text. For example, I am writing a text encryptor. The protocol provides basic tools for registering services in a client application's menu initiating the transaction fetching text from the client highlighting character ranges in the client while it is in the background replacing text in the client closing the transaction Word Services is not just for word processors. Any application that allows text editing should consider using Word Services. Usenet News clients terminal emulators Word Services provides many advantages to users and developers over traditional built-in spellers.
Users can select a single speller and dictionary to share among all their applications.
This means that disk space is required for only one dictionary, and that the user only has to teach new words to the spellchecker once. Also, a single user interface is used for spelling among all the client apps. Since Word Services is an open protocol, the user can pick their favorite server apps from several competing vendors. Word Services allows multiple servers to be installed. A user might pick servers for each of several languages, or for different functions.