gimp 2.0 - transparent

FILE > OPEN > choose picture
For shortcut use - ctrl+O

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EXAMPLE

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Use "Fuzzy Select Tools"
or
For shortcut use - U

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Important = Before that go to 

LAYER > TRANSPARENCY > click on ADD ALPHA CHANNEL

after that
"Click on the background that you want to be remove"

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press "DELETE" to remove

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After that your picture like this

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DONT forget to SAVE in PNG file

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DONT tick
like in image 9

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SAVE

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