Pro might indicate high speed, but it will depend upon the manufacturer of the card.
The word Pro is used on quite a few cards.
It does not necessarily mean anything.
Here is a link to a chart for cards used on the Canon Rebel 300D.
http://www.robgalbraith.com/bins/multi_page.asp?cid=6007-6425
The closer to the top of the list, the faster the card when used on the Canon Rebel.
Note: many Pro cards are far down on the list.
A fast card seldom makes any difference on the average digital camera. But it does make a difference on DSLR (Digital Single Lens Reflex) cameras.
If a fast card is required or suggested for a particular camera, that information will be in the User's Manual.
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Recently I was surfing the various suppliers of CD camera memory cards. Saw a great leap in price between a regular card and the Pro version.
Is the Pro version better made? Higher quality?
Any other differences?
Thanks,
Kevin

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