"OmegaT is an online translation application written in Mac language. It's an invaluable tool intended mainly for professional translators." This description, along with many others, are posted on the "About OmegaT" page of the website. I downloaded OmegaT and immediately tried out a few of its features, such as the ability to import a document from your Mac's desktop. I also tried it out with a number of documents, and it worked as expected. The software did well at translating text and documents.
However, after I downloaded OmegaT, it appeared to me that the software was designed specifically for Macs. Why is it so different from the program I used when I was using Windows? Well, Mac users don't need the translation component. What they need is a Mac-specific version of the application. This program, called "Mac Translation," is an application that you can download and install onto your Mac. Mac Translation works by translating documents to your Mac's native language. It doesn't translate for you!
It will do the job, but it won't be as good as OmegaT. It's also available for purchase. The software is available for download for free. But it isn't recommended for people who want to use their Mac to do the translation work. They need the "Mac Translation" program.