The icons you see at the bottom or top of the web page each perform a function when clicked. See below for help on each icon and try rolling your mouse (or touch if on a touch device) to see more detail on each icon
It is important to understand that when you have connected to a session, before closing the browser it helps both you and others to disconnect using the disconnect icon: 
Please note that you should always use the Print Screen 
and optionally the Save Print Screen 
Icons to print screens.
The browser or system print screen actions will not format the print correctly.
For the most reliable Clipboard Copy, use the 
icon as this can copy not only single text but also a whole section of the screen as a rectangle.
With some browsers you can highlight on a single line text and use the Ctrl-C to copy to the clipboard.
For Clipboard Pasting, the Ctrl-V works well in most situations and so does the 
Clipboard Paste icon.
Sometimes the keyboard can be locked ("LOCKED" appears in lower right of the page) -- if this happens, click on the 
Refresh Icon
The Refresh icon can be used at any time you may think the screen needs to be updated from the host.