You need software like Jasc Animation shop and Adobe Photoshop and lots of graphic designing skills as well as other abilities to make those kinds of web graphics.

http://members.aol.com/royalef/gifmake.htm
http://www.bobpowell.net/giftransparency.htm
http://www.devx.com/projectcool/Article/19997/1954?pf=true
http://www.frontiernet.net/~steve_glimpse/anidraw.html
http://www.htmltutorials.ca/lesson15.htm
http://www.infocellar.com/Graphics/16-color.htm
http://www.webwitchery.com/articles/format/
http://www.emu.edu.tr/english/facilitiesservices/computercenter/bookslib/Web%20Publishing%20Professional%20Reference%20Edition,%20William%20Stanek/ch19.htm
http://en.wikipedia.org/wiki/GIF
http://kancrn.kckps.k12.ks.us/ats/mybetti/lessons.html
http://www.webreference.com/dev/gifanim/
Please visit the above pages. I hope, it helps u.

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