while updating fedora 14 using yum,i got this message
total 91 kB/s | 28 MB 05:18
warning: rpmts_HdrFromFdno: Header V3 RSA/SHA256 Signature, key ID f09d8368: NOKEY
rpmfusion-nonfree/gpgkey | 3.4 kB 00:00 ...
Importing GPG key 0xF09D8368:
Userid : RPM Fusion nonfree repository for Fedora (14) <rpmfusion-buildsys@lists.rpmfusion.org>
Package: rpmfusion-nonfree-release-12-3.noarch (@/rpmfusion-nonfree-release-stable.noarch)
From : /etc/pki/rpm-gpg/RPM-GPG-KEY-rpmfusion-nonfree-fedora-14-i386
Is this ok [y/N]:


what does this mean ?
what should i do ?

you have to give 'yes/y' there is no harm in that.
rpmfusion-non free is nothing but the 3rd party repository, applications that are not shipped with fedora can be downloaded using RPM fusion. for more info on that go to rpm fusion

i had installed the rpmfusion-non free earlier.
thanks decodedthought
but
i what to know what exactly does this message means ?

it is basically downloading the keys for the packages which indicates the type of architecture that you are using so as to retrieve package that matches your architecture and the gpg(Gnu-privacy guard)key is used to check if the package is corrupt or fine since Fedora requires that every package is signed or else it won't install it.

"Package: rpmfusion-nonfree-release-12-3.noarch" is the package that you want to install. and the '.noarch' means that it is not architecture specific.

From : /etc/pki/rpm-gpg/RPM-GPG-KEY-rpmfusion-nonfree-fedora-14-i386 is the source from where the package and the keys are imported from.

if you want more and detailed information read the Fedora documentation.