100 exercises to learn Rust

book/src/04_traits/00_intro.md

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+# Traits
+
+In the previous chapter we covered the basics of Rust's type and ownership system.  
+It's time to dig deeper: we'll explore **traits**, Rust's take on interfaces.
+
+Once you learn about traits, you'll start seeing their fingerprints all over the place.  
+In fact, you've already seen traits in action throughout the previous chapter, e.g. `.into()` invocations as well
+as operators like `==` and `+`.
+
+On top of traits as a concept, we'll also cover some of the key traits that are defined in Rust's standard library:
+
+- Operator traits (e.g. `Add`, `Sub`, `PartialEq`, etc.)
+- `From` and `Into`, for infallible conversions
+- `Clone` and `Copy`, for copying values
+- `Deref` and deref coercion
+- `Sized`, to mark types with a known size
+- `Drop`, for custom cleanup logic
+
+Since we'll be talking about conversions, we'll seize the opportunity to plug some of the "knowledge gaps" 
+from the previous chapter—e.g. what is `"A title"`, exactly? Time to learn more about slices too!
+
+## References
+
+- The exercise for this section is located in `exercises/04_traits/00_intro`