Archive emails with a single key in Gmail
The keyboard shortcut to archive emails in Gmail is "e". But you need to first select an email before using "e" to archive your email. This is an unnecessary step that Simplehuman fixes.
With the Simplehuman extension installed on your browser, you do not need to select an email first before acting on it. You can just hit "e" on your keyboard and the currently highlighted email will be archived instantly.
The email will then be moved to your archive folder.
Install the Simplehuman for Gmail extension from https://simplehuman.email