How to reinitialize terminal (Linux, Solaris etc.)

In cases when your terminal has lost the cursor or similar you could use the OS command

reset

It will reset the special characters to their default values at least. You will not have to logoff/logon again to reinitialize your terminal session. 

P.S. You will also wish to run clear command (the shortcut for clear usually is 'Ctrl+l') before reset command as well if you need it (to clear status strings of tmux or screen sessions etc.)

Good Luck !