Yes and No. SLAX is based on Slackware, but it it a Live CD distro (meaning that it runs entirely off the CD, and does not modify data on the hard drive). Live CD's are really cool, and allow you to run a full-fledged Linux system off just about any PC that can boot from the CD. Knoppix is probably the best known Live CD.
Slackware itself though is a different distro, and if you visit the home pages of each distro, there will be plenty more info. Strictly speaking though, SLAX and Slackware are two different projects, and are not the same thing