It has taken me time to learn the Gmail shortcuts. As a web app, Gmail has to do things differently -- like not using the Command or Control keys when typing a shortcut. For those who use keyboard shortcuts every day, this can be strange. But for those who have not bothered to learn traditional shortcuts, Gmail may actually be easier. Read on for a few shortcuts you can use everyday.
Frequently Used Shortcuts
Begin by enabling Keyboard Shortcuts in your Gmail Settings (upper right corner of the Gmail window). You may need to close out of Gmail to make the settings change take effect.
When you are reading a message or a conversation and you'd like to respond, press the letter R (no need to press the Command or Control keys). This will set up a reply message and put the cursor right where you need it in the body of the message.
Like the R shortcut, pressing F will set you up for forwarding the message to someone else. Instead of putting the cursor in the body of the message, Gmail first asks you to identify who you are forwarding to. After typing a name or address, press TAB to edit the subject (if desired) and then TAB again to get to the message body.
For those who like to keep their Inbox clean, Gmail provides a very simple option called "Archive." When you archive a conversation, you take it out of the inbox and leave it in the "All Mail" folder. For those of you who understand labels, this really means it just removes the "Inbox" label. I like this since I can get messages out of the way and don't have to spend any time or mental effort deciding where to put it. It's like the big box you dump all your papers in when you clean your desk (everybody does that, right?).
Anyway, the shortcut for archiving a conversation is E. Why E? Because A is the shortcut for reply all. After reading a message/conversation, press E. Gmail archives the conversation and returns you to the Inbox.
Bonus for Advanced Users
Want to try more? Use J for previous conversation and K for the next. Or try '[' and ']' to do the same but archive the conversations at the same time.
The full list of Gmail shortcuts and descriptions can be found online or press ? when you are in Gmail.