Merriam Webster defines intellectual freedom as: freedom that allows people to think about or study what they want.
Encyclopedia of Diversity and Social Justice provides this definition:
Intellectual freedom means having the liberty to seek and express knowledge. Instead of waiting for the permission of others for intellectual advancement, one openly reads, writes, and thinks without reservation or apology.
Book banning occurs when individuals or organizations attempt to ban books or limit their availability. This has been an issue primarily in public and school libraries, and efforts to ban books continue throughout the United States.