Secure Disk lets you encrypt the content of any local or removable disc. For this it uses an AES 256-bit algorithm in the disc´s physical sector, thus protecting the content from unauthorized access.
The program works continuously at operating system level, and constantly encrypts/de-encrypts data depending on who accesses them. In other words, even if the data is extracted it remains encrypted to all who don´t have the password.
While you work on your PC, you can access the files protected with Secure Disk absolutely normally, as you have already opened it from the Secure Disk panel.