filtering software is used so as to make sure that improper ...

The Internet offers access to a wealth of material that is
personally, professionally and culturally enriching to individuals
of all ages. However, it also enables access to some material that
may be offensive, disturbing, illegal, inaccurate or incomplete.
Users are encouraged to evaluate the validity and appropriateness
of information accessed via the Internet.
Tests by the library and by independent agencies have shown that
filtering software may help to block access to objectionable
Internet sites. However, the software cannot block out all
objectionable sites, and it does sometimes block useful material,
including sites that are suitable for children, teens and adults.

Public Internet computers are equipped with commercial
filtering software. The library's filtering policy upholds the
principles of intellectual freedom, allowing adults to make their
own choices regarding filtering. The policy also aims to ensure
that our libraries are safe and welcoming places for children, and
it affirms the right and responsibility of parents to make choices
for their own children and teens.


According to the text above, it can be deduced that