What are they?
Access Keys and Secret Access Keys are designed to protect your username and password from third party systems. At anytime you can find your access key information by clicking on Settings → My Access Keys:
Access Key allow you to interact with 3rd Party software vendors through an access key instead of your username and password. This will enable you to work with other 3rd Party software applications while not handing over your username and password for the ISN. This keeps your account 100% protected and allows you to control 3rd Party Software access via your access keys. At anytime you can invalidate your keys and all 3rd Party Software applications will no longer have access to your account via ISN while you have still maintained your username and password for ISN. The 3rd Party application will specifically ask for your ISN Access Key and your ISN Secret Access Key. Both of these keys are located in Settings -> My Access Keys