cd to D Drive

If you can give the output of:

mount

We can advise. The NTFS file system (not a drive) will be mounted somewhere as a folder.

Output from the window produced by Ctrl + Alt + F2 is as follows: -

kt@kt-Aspire-7520:~$ mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=1921832k,nr_inodes=206402,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,noexec,relatime,size=387668k,mode=755)
/dev/sdb5 on / type ext4 (rw,relatime,errors=remount-ro,data=ordered)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
tmpfs on /sys/fs/cgroup type tmpfs (rw,mode=755)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event,release_agent=/run/cgmanager/agents/cgm-release-agent.perf_event)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset,clone_children)
cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb,release_agent=/run/cgmanager/agents/cgm-release-agent.hugetlb)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=30,pgrp=1,timeout=0,minproto=5,maxproto=5,direct)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime)
mqueue on /dev/mqueue type mqueue (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,relatime)
cgmfs on /run/cgmanager/fs type tmpfs (rw,relatime,size=100k,mode=755)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,relatime)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=387668k,mode=700,uid=1000,gid=1000)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)
/dev/sdc1 on /media/kt/STAL 8GB type fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other,blksize=4096,uhelper=udisks2)
/dev/sdb1 on /media/kt/Data type fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other,blksize=4096,uhelper=udisks2)
kt@kt-Aspire-7520:~$

What does NTFS stand for in this context?

Ok, if you run:

nautilus /media/kt/Data

Do you see the data? If so then add it to your favourites in Nautilus. Or (assuming it IS correct) then run:

ln -s /media/kt/Data ~/Windows\ Data

And you will see a shortcut in your home folder, you can also use:

cd ~/Windows\ Data

and see the files in a Terminal. Symbolic links are extremely powerful.

My knowledge of computers, and even more so, of ubuntu, is extremely limited.

From “Ok, if you run:
nautilus /media/kt/Data”,

I think I should use “Ctrl + Alt + T” to open the Terminal, and copy/paste “nautilus /media/kt/Data”. The result is: -
kt@kt-Aspire-7520:~$ nautilus /media/kt/Data
(nautilus:3377): Gtk-CRITICAL **: gtk_icon_theme_get_for_screen: assertion 'GDK_IS_SCREEN (screen)' failed
(nautilus:3377): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(nautilus:3377): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed
kt@kt-Aspire-7520:~$

Therefore this action has not opened my “Data” drive.

If I use Ctrl+Alt+T, and copy/paste “cd ~/Windows\ Data” from your reply, then I get: -

kt@kt-Aspire-7520:~$ cd ~/Windows\ Data
bash: cd: /home/kt/Windows Data: No such file or directory
kt@kt-Aspire-7520:~$

Please, where to next?

Did the symlink not work?

If you navigate (in Nautilus) to

/media

You will see mounted file systems there, one will be your data folder.

Andrew - Thank you for your help.

However it all got too complex for me, because I am a computer user, not a computer expert. Even the Terminal left me cold, because I could not find a simple explanation of what it is and what it is used for. When it did not do what the instructions said it would do, I was lost. In addition, I had to wade through numerous Google entries to try to find out what "Nautilus" is, and what it does. The ubuntu help function leads to the "Ubuntu Desktop Guide", which does not have a "search" box. Ubuntu pages tend to go straight into great technical depth.

I haven't a clue what a "symlink" is.

So, with my limited knowledge of computers, and ubuntu, I have abandoned any thoughts of using "Terminal". I shall continue trying to use ubuntu, because it starts up faster than Windows. However, I am struggling.

What you write is somewhat contradictory.
You are looking for a "cd" command in a terminal, but write that you are not used to working with the terminal.

+++++

Main difference with respect to drives between Windows and Ubuntu:

On Windows each partition has a separate drive letter C: D: etc (limited to 26, what to do then?)

On Unix systems like Ubuntu, there are no drive letters, but there is only one directory tree that spans all disk partitions.
The root of it is called /
below this there are the home directories (below /home), the executable programs (below /bin) etc.

If you want to access an additional disk partition (like your HD for downloads and programs), you have to connect that file system to your directory tree. This action is called mounting. Usually you do not have to bother much about the details, because Ubuntu has an automount feature and does everything itself.

Open the file explorer program in Ubuntu (by clicking on the respective icon on the left hand side, usually second from top).
You will see the contents of your home directory in the right half of the window.
On the left hand side of the file explorer window you should see some shortcuts and the data partition listed (in the lower part), like this: http://i.stack.imgur.com/tv6OC.png
Just clicking on the icon should show its contents on the right hand side.

Manfred - Thank you for your explanation.

I was using the "Terminal" following some advice from "actionparsnip", without really having any idea what I was doing.

I think I now vaguely understand the ubuntu way of listing drives, directories, partitions, folders, programs and files although this has taken many hours and false trails. Windows Explorer is much easier for the newbe to understand.

That "Files" icon actually opens a list of Folders and Drives, which anyone coming from "Windows" will not see as "Files". I don't want most of the "Files", although they won't go away, even when I delete them in "Home". (The RH Click/"Delete" choice in the "Files" list is greyed out.)

Hey ho - forever onwards.