Gmail has always been the best email providing service and hence people usually receive so many mails in a day that checking one mail and than getting back to the inbox for checking another one is a tedious task and hence consume a lots of time, well now using Preview Pane Gmail labs beta feature you can take away that thing but just clicking on the mail and getting its preview on the right hand side without any loading check below screenshot.
So as you can see I just clicked on the mail and I got its preview rendered on the right hand side window. So now I can cycle through all my mails one by one and check their previews instantly and yet you can reply and forward everything right from that right hand side window.
How to Install Preview Pane Feature in Gmail :
Well to install preview pane in Gmail you just need to open up your Gmail account and than head over to Settings > Labs > Preview Pane, enable it and click on save.
Now your Gmail will refresh automatically getting this beta feature into work, and it will be live so you can try checking it out by clicking on any email in your inbox and it will load in the right hand side window.