Final answer:
The feature in a software package that periodically checks for updates on the vendor's website is known as an automatic update feature. It helps maintain the security and functionality of the software.
Step-by-step explanation:
The software package feature that periodically checks the vendor’s website for software updates is called an automatic update feature or updater. This feature runs in the background of your system and ensures that your software is always up to date by automatically downloading and installing updates when they are available.
This is an important feature for maintaining software security and functionality, as updates may contain important patches for security vulnerabilities or improvements in the software. Generally, you can adjust the settings of this feature to decide how often it checks for updates and whether it should notify you before downloading or installing them.