exif data not saved - macos

i wonder why when i save any jpg image from internet the EXIF data is gone or not saved?
i am developing a photo gallery website so i download sample photos from the net as testing, mostly from flickr.
i only download photos that have exif data, but once saved in my mac, the exif is removed or not saved. at first i thought my wordpress exif plugin is not working but when i check the exif locally in my mac, the exif data is not there.

that's because most operations done on an image will wipe the exif data
if you want to download the pictures from flicker while keeping the exif you will need to go (on the picture page) to Actions => All sizes => download original
if you do that you can keep the exif.
but for testing purposes what I do personally is to grap any picture from google image and than stamp the exif data using a stamping software myself. This way, I will know whether the data that I'm getting are correct or not.
BTW, I have just finished a week ago from developing a gallery website using wordpress for a client, so if you faced any problems specially in the exif part, feel free to ask

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You were correct kingsvid!

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