32 Bit Applications
The central processing unit (CPU) of a computer processes the code that you run on the computer. In the past, when an application hands off chunks of code to the CPU for processing, it limited the size of those chunks to 32 bits. We call this style of computing “32 bit”.
With the advent of 64 bit processors, it has become common for applications to speak to processors in chunks of (as you might guess) 64 bits.
Functionally, there is little difference, but basically all new computers at this point ship with 64 bit CPUs, and the code required to enable more than 4gb of RAM with a 32 bit CPU is generally regarded as non-optimal, so if you are faced with the choice between Slackware and Slackware64, you should probably opt for Slackware64 (assuming, of course, that you're using a 64 bit CPU).
Slackware64 is multilib-ready, meaning it is capable of running 64 bit as well as 32 bit software. However, Slackware64 does not ship with any 32 bit software. Most modern technology is starting to favour 64 bit architecture, so you probably won't have any need to run 32 bit software, but there are those times when you are forced into running 32 bit for legacy support (usually for non-open source applications, since open source code can just be re-compiled for 64 bit). If you find it necessary, for whatever reason, to run 32 bit software, then you will need to enable multilib on your Slackware64 system:
- Switch to multilib versions of glibc (a glibc version that supports running both 32bit and 64bit binaries)
- Use a multilib version of gcc (to compile 32bit binaries as well as 64bit binaries)
- Install system libraries from 32bit Slackware to create a 32bit software layer
This has all been masterminded by AlienBob; follow his step-by-step instructions on his wiki.