---
id: c-variables-names
title: "C Variable Names (Identifiers)"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["identifiers", "camelCase", "C 변수 이름 규칙"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.85
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["c", "programming-language", "w3schools", "variables", "naming"]
raw_sources: ["https://www.w3schools.com/c/c_variables_names.php"]
applied_in: []
github_commit: ""
---

# [[C Variable Names (Identifiers)]]

## 🎯 한 줄 통찰 (One-line insight)
Variable names in C are strictly CASE-SENSITIVE at the identifier level — `myVar` and `myvar` are two completely distinct variables, not a warning or a style issue — meaning a single accidental capitalization typo silently creates a second, separate variable rather than referencing the intended one, a class of bug the compiler won't catch as a naming error. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Identifier** — the unique name given to a variable. [S1]
- **Naming rules** — letters, digits, and underscores allowed; must begin with a letter or underscore; case-sensitive; no whitespace or special characters (`!`, `#`, `%`, etc.); reserved words (e.g. `int`) cannot be used as names. [S1]
- **Descriptive naming recommended** — `minutesPerHour` over `m`, for maintainability, even though both compile correctly. [S1]
- **Two common naming styles** — camelCase (`totalScore`) or underscore-separated (`total_score`); the source recommends picking one and staying consistent. [S1]

## 📖 세부 내용 (Details)
- Valid names: `age`, `_count`, `totalSum`. [S1]
- Invalid names and why: `1age` (starts with a digit), `my-age` (contains a hyphen), `int` (reserved word). [S1]
- Descriptive vs terse naming contrast: `int minutesPerHour = 60;` (clear) versus `int m = 60;` (compiles, but unclear intent). [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- **대소문자 구분의 함정**: myVar와 myvar가 서로 다른 변수로 취급된다는 점이 명시되며, 이는 오타로 인한 미묘한 버그의 원인이 될 수 있다는 점을 시사함. [S1]

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — camelCase나 언더스코어 스타일 중 하나를 프로젝트 전체에 일관되게 적용하는 것이 실전 코드 컨벤션의 기본이다. [S1]

## 💻 코드 패턴 (Code patterns)
Descriptive vs. terse variable naming (C):
```c
// Good variable name
int minutesPerHour = 60;
// OK, but not so easy to understand what m actually is
int m = 60;
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.85
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[C Tutorial]]
- **관련 개념:** [[C Variables]], [[C Variables Change]]
- **참조 맥락:** 변수 이름 규칙 — 변수 값 변경(Variables Change) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — C Variable Names (Identifiers) — https://www.w3schools.com/c/c_variables_names.php

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "C Variable Names (Identifiers)" page (Astra wiki-curation, P-Reinforce v3.1 format).