Red hat
- For the corporation that produces Red Hat Linux, see Red Hat.
- For the lineage of Tibetan Buddhism known as Red Hat Lamas, see Shamarpa.
- The red hat is one of Edward DeBono's Six Thinking Hats.
The term red hat when used within the Roman Catholic Church refers to the appointment of a Cardinal, a senior Prince of the Church who is a member of the electoral college that chooses the Pope. A person on being appointed to the cardinalate is said to have received the red hat or cardinal's biretta. Cardinals created in each consistory through that of 1967 received a broad-brimmed, tasseled hat as a symbol of their office—the galero. Today, Cardinals no longer receive the galero (in Latin galerum rubrum), which they would wear only once while cardinal and which would be hung up in their former cathedral on their death and left to disintegrate through decay and old age, symbolising the passing of manmade glories and power. Today, the Cardinals receive a red biretta (a 4-pointed hat) at the consistory. Sometimes a galero is obtained privately for the cardinal and the old ceremony is observed on their deaths.