What program/software are they using for creating moving graphics?

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If you are a PTC ads clicker, you will see lots of moving graphics. I was thinking, do you have any idea what softwares they were using?There are tons of people who submitted their own design and graphics, that's why it seems to me that there is a certain GIF program or website design tools software that is easy to use, which can be used by anyone without much advance background in graphics. I am familiar with the Macromedia tools, but I think, there are using a more simple one. I am interested to know what product is this, so if you have any idea, please let me know. Thanks!