For the longest time I thought "tr" stands for "trim", but it actually means "translate". And this video shows that name makes a lot of sense. You can use tr to transform characters (e.g. lower to upper). Additionally you can remove specific characters (e.g. trim spaces) or you could even filter anything that doesn't match a specific matcher, such as alpha-numeric characters.

Learn how to use the tr command in this latest terminal tutorial! Enjoy!