This is just a quick but useful tip I have come across over the last couple of days. In a nutshell when you view emails in Mail, you get the latest one first, followed by the second and so on, the order depends on how you have set them out. This is fine most of the time, but if you are tracking an email conversation it may become difficult to follow. This is where thread view comes into play.
Thread view changes the way Mail shows you emails. It is common in applications such as Gmail and Unison. To turn thread view on, go to View > Organise By Thread. This will go through your Mail box and set any emails with the same author and subject into a group. When you click on a group you get all of the emails. This shows you all of the replies and messages for a particular subject. It allows you to quickly track a conversation. Normally you would have to scroll through replies and see what people have quoted.
Any time you click on the first email within a list, Mail will set the view pane to show a summary of the emails sent. This is another quick way to see emails.
Once you have enabled this option the view menu allows you to use two more options. Expand All Thread and Collapse All Threads, it is pretty self explanatory what each one does.
Thread view allows you to begin hiding messages and compressing down your inbox. I find it is a great way of keeping track of email conversations at the same time making things easier to find. If you ever want to turn this feature off, simply select the Organise By Thread option again and it will revert to normal.
If you have any tips or tricks similar to this then please leave a comment below. If you are interested in further reading take a look at Take Control of Apple Mail on Amazon.