This helps prevent automated programs from misusing this service.

Its lack doesn't prevent programs from coming into existence, it just maybe slows down their development a little.

Doing so helps prevent automated programs from abusing this service.

This prevents programs from having any meaningful opening book.

This prevents automated programs from posting comments.

Unseen, but hard at work, is an elaborate encryption system that prevents programs from being downloaded without authorization.

Network firewalls prevent unknown programs and processes from accessing the system.

This prevents programs running in protected mode from interfering with each other's memory.

Prevent programs from writing to disk.