Firefox fails to open

When i click on to open Firefox, it do not opens.what's wrong?

Type firefox in your xterm

Type firefox in your xterm and look for error messages.You may move your profile in ~/.mozilla/firefox/ to ~/.mozilla/firefox-original/ and create a new one at the next startup.Sometimes faulty plugins cause the firefox to crash. Move the plugins-directory in /opt/firefox, /usr/local/firefox or similar.If firefox runs as root you may have to change the owner and permissions.