That'* what color brake fluid turns when it gets old and has rust and water in it. Brake fluid absorbs water from the air, I forgot the 'technical' term for that. Your brake system parts can actually rust out and seize up from the dirty fluid.
It'* old and you should bleed the brakes until it'* comes out clear. It'* not that hard to do, and I get a satisfaction from doing it, knowing that the fresh fluid will allow the brake parts to last longer and the brakes to work better. Brake fluid is cheap too.
When you do it, you'll be amazed how dark and dirty the fluid is compared to new brake fluid.
1996 Olds LS, 198,900 miles: RIP...