Many desktop environments define a long list of "shortcuts" or "hot keys" by default. Many of which you never use and may not even be aware of. As an emacs user it is good to unbind the ones you don't use; both for the obvious reason that emacs can now use those key sequences, but also because when using emacs (and therefore pressing (Esc Meta Alt Ctrl Super) often), you will be much more likely to accidentally type shortcut key sequences.
I use debian linux with the xfce desktop environment so I use that as an example. Xfce (version 4 at least) has a menu under Application/Settings/Window Manager/Keyboard where you can turn off keyboard shortcuts. I like to use alt tab to cycle windows, but I turn most of the other bindings off.
The details of keyboard configuration depend on the operating system you use.
For linux users the main tools are xkbcomp and xev. I suggest
this explanation on archlinux.org.
The details are bit complicated, but it is worth the effort to be able to make your
keyboard do what you want.
Emacs and key sequences
key presses = function call
In any application that responds to the keyboard, user key presses somehow
affect the execution of the application. In Emacs this relationship is
transparent and accessible to users.
The flexible key binding facility of emacs is one of its strong points.
In emacs-speak, a "command" is simply a function which can be called via
pressing a key (or doing something with the mouse etc).
The command execute-extended-command, with default key binding M-x
can be used to invoke commands by name; where M-x denotes the key sequence:
hold the alt key down and then press x (or alternatively press Esc
and then press x. For example try pressing M-x and entering
forward-char at the prompt. In most types of buffers, it should have the effect of moving the cursor
forward one position.
At the start the most important functions to know are:
If you use emacs a lot, eventually you will want to change your key bindings for all kinds of commands: built-in commands, commands you import from packages, and commands you write for yourself. A nice feature of describe-function is that links to the implementation of any emacs function (or special form) even if it is implemented in C (See viewing emacs C src code).
I hope to write a section on key binding soon...
One can use C-h or the F1 key to display all completions of a prefix key (or more generally a prefix sequence).
Suppose for example, you are curious to know what key bindings start with C-x. An easy way to
display that information is to press C-x followed by C-h or F1, which should cause
emacs to display information about key bindings starting with C-x in a *Help* buffer.
The prefix sequence can be more than just a single key, for example try C-x 8 ' C-h to see some commands
for inputting letters with acute accents such as Á and ý.
Alternatively, one can use the describe-keymap command if you know the name of the relevant keymap
(ctl-x-map for example).