I need install
libjpeg.so.8 to CentOS 6.6 but i do not understand how to do...
I have installed
libjpeg.so.8 there is not
It depends on why you want that particular version. CentOS 6 has /usr/lib64/libjpeg.so.62
Some applications may require a specific old version. A forum comment pdf2swf and libjpeg.so.8 problem stated that a solution was found by adding the rpmforge repository and getting the library from that location (using this page).
Just had this specific problem, wanted to install "Genymotion" software on Fedora 23. This is proprietary software and you can't just recompile it against a different version of this lib, so I compiled libjpeg 8.0 from source. You can grab it here (64bit only).
Remember that using binaries from random people on Internet is probably a bad idea. ;)