The buttons in the yellow area above serve to compare the efficiency of simply concatenating strings and
writing them into a document with that of appending strings to the end of an array,
and then converting the array to a string and writing that to a document. Generally, you will probably
find the latter approach faster (except in the Opera browser). The differences become more pronounced
as the size of the string increases.
The techniques considered are as follows:
(Note: try this in Opera 9.0 -- it is really fast)