comprehensive-rust/src/basic-syntax/scalar-types.md

Scalar Types

	Types	Literals
Signed integers	i8, i16, i32, i64, i128, isize	-10, 0, 1_000, 123i64
Unsigned integers	u8, u16, u32, u64, u128, usize	0, 123, 10u16
Floating point numbers	f32, f64	3.14, -10.0e20, 2f32
Strings	&str	"foo", r#"\\"#
Unicode scalar values	char	'a', 'α', '∞'
Byte strings	&[u8]	b"abc", br#" " "#
Booleans	bool	true, false

The types have widths as follows:

• iN, uN, and fN are N bits wide,
• isize and usize are the width of a pointer,
• char is 32 bit wide,
• bool is 8 bit wide.