I'm using Ubuntu 14.04.2 LTS \n \l.
Here are the libcs I installed.
$ dpkg --list | grep libc6
ii libc6:amd64 2.19-0ubuntu6.7 amd64 Embedded GNU C Library: Shared libraries
ii libc6-dbg:amd64 2.19-0ubuntu6.7 amd64 Embedded GNU C Library: detached debugging symbols
ii libc6-dev:amd64 2.19-0ubuntu6.7 amd64 Embedded GNU C Library: Development Libraries and Header Files
ii libc6-i386 2.19-0ubuntu6.7 amd64 Embedded GNU C Library: 32-bit shared libraries for AMD64
rc libc6-x32 2.19-0ubuntu6.7 amd64 Embedded GNU C Library: X32 ABI Shared libraries for AMD64
But when I do $ sudo apt-get install libdbus-1-3:i386
The following errors show up
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
libdbus-1-3:i386 : Depends: libc6:i386 (>= 2.10) but it is not going to be installed
unity-control-center : Depends: libcheese-gtk23 (>= 3.4.0) but it is not going to be installed
Depends: libcheese7 (>= 3.0.1) but it is not going to be installed
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
I'm wondering what's the difference between libc6:i386 and libc6-i386?
libc6:i386 is the i386 version of libc for i386 architecture kernels/systems. This is for running packages built for i386 systems and would be required if you are trying to use i386 packages on an amd64 system. This is called multiarch.
libc6-i386 is the 32bit development package of libc for amd64 systems. This is not for running software, its for compiling and linking 32 bit code.
来源：https://stackoverflow.com/questions/37313639/whats-the-difference-between-libc6i386-and-libc6-i386