Dictionary

Tailwind CSS is a utility-first CSS framework that provides low-level utility classes like `flex`, `pt-4`, `text-center`, and `bg-blue-500` to build designs directly in your markup. Instead of writing custom CSS, you compose pre-built classes to create any design, which results in smaller final CSS bundles thanks to automatic purging of unused styles. Its configuration file allows full customization of the design system including colors, spacing, breakpoints, and typography.

A toast notification is a small, non-intrusive message that appears briefly on screen — usually at the top or bottom — to provide feedback about an action without interrupting the user's workflow. Unlike modals, toasts auto-dismiss after a few seconds and don't require user interaction. They are commonly used to confirm saves, report errors, or show status updates. Accessible implementations include ARIA live regions so screen readers announce the message.

In the context of AI language models, a token is the basic unit of text that a model processes — typically a word, subword, or character depending on the tokenizer. LLM pricing, context windows, and rate limits are all measured in tokens. Understanding tokenization is essential for optimizing costs and staying within model context limits when building AI-powered applications.

The transformer is a neural network architecture introduced in the 2017 paper "Attention Is All You Need" that revolutionized natural language processing. Unlike recurrent networks, transformers process entire sequences in parallel using a self-attention mechanism, which allows them to capture long-range dependencies efficiently. Virtually all modern LLMs, including GPT and Claude, are built on the transformer architecture.

Tree shaking is a dead code elimination technique used by modern bundlers like Webpack, Rollup, and esbuild to remove unused exports from the final JavaScript bundle. It relies on the static structure of ES module `import`/`export` syntax to determine which code is actually referenced and safely discard the rest. For tree shaking to work effectively, libraries must use ESM format and avoid side effects in their module initialization, which is why the `sideEffects` field in `package.json` matters.

Turbo Modules are the next-generation native module system in React Native's New Architecture, replacing the traditional bridge-based modules. They use the JavaScript Interface (JSI) for direct, synchronous communication between JavaScript and native code, eliminating the serialization overhead of the old JSON bridge. Turbo Modules also support lazy loading — they're only initialized when first accessed rather than at app startup, which significantly improves launch performance.