Java applets are pieces of Java bytecode that are loaded from the server into the
web page on the user's computer. So the code is executed on the machine of the user and
not on the server.
Usually applets are used for not-too-large programs, as the loading time
(e.g. complicated dynamic graphical interfaces) or when calculations have to be performed
Java applets are less used when connection to a SQL-database has to be established (although this
is perfectly possible).
Computer Chemistry Consultancy, June 2001