From Wikipedia.com:

Freedom of speech is the freedom to speak without censorship and/or limitation. The synonymous term freedom of expression is sometimes used to indicate not only freedom of verbal speech but any act of seeking, receiving and imparting information or ideas, regardless of
the medium used. In practice, the right to freedom of speech is not absolute in any country and the right is commonly subject to limitations, such as on "hate speech".
The right to freedom of speech is recognized as a human right under Article 19 of the Universal Declaration of
Human Rights and recognized in international human rights law in the International Covenant on Civil and
Political Rights (ICCPR). The ICCPR recognizes the right to freedom of speech as "the right to hold opinions without interference. Everyone shall have the right to freedom of expression". Furthermore freedom of speech is recognized in European, inter-American and African regional human rights law.