How to install Dropbox in ubuntu 14.04 LTS

1. Download the .deb file from Internet, the website link is here: Install dropbox on your linux box. (There are some instructions in official about how to install dropbox from command line). An alternative way to download dropbox is as follows:
   32bit download
   $ wget https://linux.dropbox.com/packages/ubuntu/dropbox_1.6.2_i386.deb
   64bit download
   $ wget https://linux.dropbox.com/packages/ubuntu/dropbox_1.6.2_amd64.deb
   
2. Get into the folder which contains the .deb file about dropbox downloaded from website.
   
3. Enter superuser privilege:
   $ sudo su
   
4. input the password.
   
5. Start to install dropbox:
   
   # dpkg -i [filename.deb]
   
6. exit the superuser privilege:
   
   # exit
   
7. get into the /usr/bin folder:
   $ cd /usr/lib
   
8. Starts the dropbox daemon, dropboxd. If dropboxd is already running, this will do nothing
   $ dropbox start -i
   
9. then dropbox will start to install on you ubuntu system