| Subject | English | Welsh |
| comp., MS | data type | math data (A property of a field that defines the kinds of data the field can store) |
| comp., MS | Double data type | Math data dwbl (A fundamental data type that holds double-precision floating-point numbers. It's stored as a 64-bit number ranging in value from approximately -1.797E308 to -4.940E-324 (negative), from 4.94E-324 to 1.797E308 (positive), and 0) |
| comp., MS | enumerated data type | math o ddata rhifol (A data type consisting of a sequence of named values given in a particular order) |
| comp., MS | Long data type | Math o ddata hir (A fundamental data type that holds large integers. A Long variable is stored as a 32-bit number ranging in value from -2,147,483,648 to 2,147,483,647) |
| comp., MS | Single data type | Math o ddata unigol (A data type that stores single-precision floating-point variables as 32-bit (4-byte) floating-point numbers ranging in value from -3.402823E38 to -1.401298E-45 for negative values and 1.401298E-45 to 3.402823E38 for positive values) |
| comp., MS | String data type | Math o ddata testun (A fundamental data type that holds characters, one character per 2 bytes. A fixed-length string can contain 1 to 64K characters; a variable-length string can contain 1 to 2 billion) |