CIPA applies to schools and libraries that receive E-rate discounts or certain other federal funds, requiring them to adopt internet safety policies and filter or block access to obscene or harmful content. It is important for people attending schools and libraries to know which ones must comply with CIPA, as those institutions have restrictions on internet access, while others may not. There are legal and technical challenges in defining what content should be filtered and ensuring filters do not block constitutionally protected speech.