GRUB QUESTION 2

Dear Experts,

I use LINUX REDHAT in Virtual Box invironment. Yesterday I tried to play with GRUB.
Then I am in a depression of what I did. After I restart LINUX in initial stage of startup
there was display as below :
GR GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB UB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB
GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB GRUB
I am not familiar with technical things in LINUX. I am student in this.
I Probably I remember what I have done.
First I typed in command line :
/sbin/grub-install /dev/hda1
Secondly I typed : /dev/hda1

Did I damaged GRUB? Dear experts! Please help me. Normally how to repair once I face problem in startup? I want to know how to handle GRUB.