The Text Area is where the messages are shown.
Selecting text then releasing the mouse will automatically copy the text to the clipboard.
This behavior can be changed in the Messages Options.
Note: for technical reasons, it's not possible to select text while scrolling.
Various things are clickable as links such as nicks, channel names and regular links.
Double-clicking a channel name joins that channel.
Right-clicking a channel name opens the scripted ChannelLink menu for this channel name.
Right-clicking a channel name opens the scripted Link menu for this link.
Right-clicking in any other area opens the scripted Channel menu for the current channel.
All the menus can be customized in the Menu Editor.
It is possible for the Text Area to show inline images, see Inline Images Options for more information.
Note: the Text Area is not a webbrower, it cannot show videos or html previews. it's like a notepad with colors.