Slackware is the true Unix of Linux distros

(subject is quoted from the vector linux website with the small edit that I replaced "distributions" with "distros" to fit in the character limited subject line)

What exactly does that mean? More importantly to me, how does slackware differ from normal linux distributions? What differences will I see?

No, it's true. It's stable, minimal, uses the most commonly expected filesystem layout, BSD-style init, and doesn't attempt to reinvent the wheel.

However, that's a mixed blessing. Don't use it as a desktop, unless you're a control freak.