1. bytes are 8 bits
2. shorts are 16 bits
3. ints are 32 bits
4. longs are 64 bits
5. arithmetic is 2's complement
6. IEEE floating point
and a big chunk of wasted time trying to abstract these away and getting it wrong anyway was saved. Millions of people cried out in relief!
Oh, and Unicode was the character set. Not EBCDIC, RADIX-50, etc.
1. u8 and i8 are 8 bits.
2. u16 and i16 are 16 bits.
3. u32 and i32 are 32 bits.
4. u64 and i64 are 64 bits.
5. Arithmetic is an explicit choice. '+' overflowing is illegal behavior (will crash in debug and releasesafe), '+%' is 2's compliment wrapping, and '+|' is saturating arithmetic. Edit: forgot to mention @addWithOverflow(), which provides a tuple of the original type and a u1; there's also std.math.add(), which returns an error on overflow.
6. f16, f32, f64, f80, and f128 are the respective but length IEEE floating point types.
The question of the length of a byte doesn't even matter. If someone wants to compile to machine whose bytes are 12 bits, just use u12 and i12.