# π§ Universal Hex Relationships (UHR)
**UHR** is the relationship layer of the Universal Hex (UHX) framework. It encodes how two UHT-encoded entities relate to each other using a fixed-width, 8-bit **semantic fingerprint**.
Each bit corresponds to a distinct relational trait, enabling **self-describing links** in system models.
---
## π UHR Basics
- **Length:** 8 bits (1 byte)
- **Format:** Binary (`10100101`), Hex (`A5`), or trait list
- **Purpose:** Describes the **type and nature** of the relationship between two entities
- **Use:** Attach UHR codes to links in semantic graphs or system models
---
## π§ UHR Trait Table
| **Bit** | **Trait Name** | **Description** |
| ------: | ------------------------------- | -------------------------------------------------------------------- |
| 1 | **Directional** | Relationship flows one way (A β B). If false, the link is symmetric. |
| 2 | **Causal / Influential** | A causes or influences B. |
| 3 | **Hierarchical / Containment** | A contains or dominates B structurally. |
| 4 | **Symbolic / Representational** | A stands for or models B. |
| 5 | **Governed / Constrained** | The link is defined or limited by external rules or systems. |
| 6 | **Temporal / Sequence-bound** | Relationship depends on time or order. |
| 7 | **Context-sensitive** | Only valid in certain conditions, environments, or perspectives. |
| 8 | **Non-reciprocal** | B does not reciprocate the relationship. |
---
## π Examples
### 1. **Feeds β**
```text
UHR: 11000001 (binary) = C1 (hex)
Traits: Directional, Causal, Non-reciprocal
Meaning: A provides input or effect to B, unidirectionally.
```
### 2. **Symbolizes β**
```text
UHR: 10001001 = 89
Traits: Directional, Symbolic, Non-reciprocal
Meaning: A represents or encodes B.
```
### 3. **Constrains β**
```text
UHR: 10100101 = A5
Traits: Directional, Governed, Non-reciprocal
Meaning: A limits or regulates B under some policy or rule.
```
### 4. **Belongs to**
```text
UHR: 00100000 = 20
Traits: Hierarchical only
Meaning: A is a part or component of B.
```
---
## π Use in Modeling
### In UHX Graphs
```markdown
Sensor [UHT: C3F20000]
Controller [UHT: C2FA3FDF]
Sensor --> Controller [UHR: C1 | Feeds β]
```
### In SDRs
```yaml
required_links:
- relation: "Feeds β"
uhr: "C1"
target_must_have: [11] # Logic processor
```
---
## π Relationship Logic
- **Symmetry**: If `Directional = 0`, the link is bidirectional (e.g., symbolic reflection)
- **Asymmetry**: `Non-reciprocal = 1` β A affects B, but not vice versa
- **Structural Semantics**: Hierarchy, containment, and symbolic relations can all be encoded
---
## π When to Use UHR
Use UHR when you want to:
- **Model how entities interact**
- **Specify required relationships in an SDR**
- **Infer emergent system behavior**
- **Document architecture patterns with meaning**
---
## π§Ή Example Relationship Network
```text
User --[C1 | Triggers β]--> Light Switch
Light Switch --[C1 | Activates β]--> Light Bulb
Power Supply --[C1 | Feeds β]--> Light Switch
```
Each arrow carries **semantic type information** β not just a line on a diagram.
---
## β
Summary
- **UHR** gives **meaning** to links in a system graph
- Each UHR code is a compact semantic descriptor (8 bits)
- Combine UHT + UHR to build fully self-describing models
- Enables **traceability, explainability, and validation** of system relationships