Basic / Arithmetic Types

• Bool
• Int
  • Int8, Int16, Int32, Int64
  • UInt, UInt8, UInt16, UInt32, UInt64
• Byte
• Float
  • Float16, Float32, Float64

Notes

It is Bool, not bool nor Boolean.

Simply use Int (that is Int64, like in Swift and Go),

• not Size, SSize, nor PtrDiff,
• not Long nor LongLong.

Int is Int32 on systems with a 32-bit address bus only (i.e. old/small platforms, like Win32/x86),
Int is Int16 on systems with a 16-bit address bus (i.e. very old/small microcontrollers like AVR/ATmega328/Arduino Uno, 6502, Z80).

Byte is std::byte, i.e. not the same type as UInt8 for parameter overloading.

Float is Float64 / double precision (like in Python, unlike C/C++).
Float is Float32 on old/small platforms only (i.e. those with hardware support for Float32 but not for Float64).
With modern processors double precision is very fast. When concerned with memory bandwidth, cache size, and SIMD performance, choose one of the smaller floating-point types like Float32 or (if available) BFloat16, Float8, maybe even Float4.