**Skill-code link.** No tick boxes live on this page, but the reasoning codes — C629 (*outlines*), C638 (*identifies*), C645 (*describes*), C658 (*explains*) — draw their "why" from these characteristics. "float: money needs decimal places" is a storage argument; "CSV: rows of identical fields" is a structure argument.

| Data type/structure | Input | Storage | Output |

|---|---|---|---|

| **Character** | Single symbols via keyboard or data files | Numeric codes (e.g. ASCII, Unicode) in memory | Visual symbol representation on screens or printed formats |

| **String** | Sequences of symbols via user input or data files | Sequence of character codes in contiguous memory, possibly with length or null terminator | Readable format of characters maintaining original order |

| **Integer** | Decimal representation from users or data sources | Binary format in a fixed number of bits | Decimal or other numeral systems for human readability |

| **Floating point** | Decimal input with fractional parts | Stored as a base, exponent and sign (e.g. IEEE 754 format) | Decimal or scientific notation respecting precision |

| **Date/time** | Various string formats or graphical UI selection | Large integer (timestamp) or separate components (year, month, day, etc.) | Formatted strings according to desired date/time format |

| **One-dimensional array** | Sequential or individual inputs at specific indices | Contiguous memory locations maintaining order by index | List or sequence format in a readable layout |

| **Two-dimensional array** | Row by row or column by column with two indices | Row-major or column-major order in contiguous memory | Tabular format respecting row and column structure |

| **Record** | Separate input for each field with varying types | Aggregates of fields in memory, sequential or aligned | Key-value formatted listing of fields and corresponding values |