Banning: the removal of challenged materials (source: the ALA Office for Intellectual Freedom)
Censorship: a change in the access status of material, based on the content of the work and made by a governing authority or its representatives. Such changes include exclusion, restriction, removal, or age/grade level changes. (source: the ALA Office for Intellectual Freedom)
Challenge: an attempt to remove or restrict materials, based upon the objections of a person or group. [...] Challenges do not simply involve a person expressing a point of view; rather, they are an attempt to remove material from the curriculum or library, thereby restricting the access of others. (source: the ALA Office for Intellectual Freedom)
Hate Crimes: the FBI has defined a hate crime as a “criminal offense against a person or property motivated in whole or in part by an offender’s bias against a race, religion, disability, sexual orientation, ethnicity, gender, or gender identity,” including skin color and national origin. Hate crimes are overt acts that can include acts of violence against persons or property, violation or deprivation of civil rights, certain "true threats," or acts of intimidation, or conspiracy to commit these crimes. (source: the ALA Office for Intellectual Freedom)
Hate Speech: there is no legal definition of "hate speech" under U.S. law, just as there is no legal definition for evil ideas, rudeness, unpatriotic speech, or any other kind of speech that people might condemn. Generally, however, hate speech is any form of expression through which speakers intend to vilify, humiliate, or incite hatred against a group or a class of persons on the basis of race, religion, skin color sexual identity, gender identity, ethnicity, disability, or national origin. (source: the ALA Office for Intellectual Freedom)
Intellectual Freedom: the right of every individual to both seek and receive information from all points of view without restriction. It provides for free access to all expressions of ideas through which any and all sides of a question, cause or movement may be explored. (source: the ALA Office for Intellectual Freedom)