I am a recent convert to the Mac, very pleased! My PC had a Microsoft "Image Resizer" that was a free download from their site that made high rez images smaller for email and the like. Does such an application exist for the Mac?
Yes. It's called "preview.app" and you already have it on your Mac. Learn how to use this app as it's a "jack of all trades" app that can do many things. And welcome to the Mac-Forums.
Hello - you've already been instructed to use Preview which is a powerful OS X built-in app already available for your use - take a look at this Apple Support Article for a review of some of its features.
BUT, just to get you started w/ some visual aids - first image below is of my den bar opened in Preview - the Toolbox (or Markup) icon (blue arrow) will open the menu bar below; the red arrow points to the 're-size' option which is opened in the second image - there size can be easily adjusted. Also, note that there are many other choices in the menu bar in the first image - that's how I added the arrows and changed their colors. Explore this utility and you will likely not need much else for your basic image edits; also a great PDF reader - Dave
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