Are preloaded images downloaded again if the preloader is called again?

Are preloaded images downloaded again if the preloader is called again?

References

Reference NO 1

http://stackoverflow.com/questions/15191139/are-preloaded-images-downloaded-again-if-the-preloader-is-called-again

Reference NO 2

http://stackoverflow.com/questions/16817676/improve-basic-script-to-preload-images

Reference NO 3

http://www.yourhtmlsource.com/images/preloading.html

Reference NO 4

http://www.javascriptkit.com/javatutors/preloadimagesplus.shtml

Reference NO 5

http://www.htmlgoodies.com/tutorials/web_graphics/article.php/3480001/So-You-Want-To-Pre-Load-Huh.htm

Reference NO 6

http://www.stevesouders.com/blog/2013/04/26/i/

Reference NO 7

http://fragged.org/preloading-images-using-javascript-the-right-way-and-without-frameworks_744.html

Reference NO 8

http://www.angelfire.com/nv/davepage/javascript.perf.html