Ollama is the most widely adopted platform for running open-source large language models locally on personal computers and servers, with optional cloud scaling for heavier workloads. Originally launched as a developer-focused command-line tool, Ollama has grown from a hundred thousand downloads to over fifty-two million monthly downloads by mid-2026, and from twelve thousand GitHub stars to more than one hundred and fifty-eight thousand, making it the de facto standard for local LLM inference. The platform lets users pull and run frontier open models like Llama 3.3, Qwen 3, DeepSeek R1, Gemma 3, Mistral, Phi-4, and many vision and reasoning models with a single command, with no GPU configuration, environment setup, or model conversion required. In 2026, Ollama added native multimodal vision support across Qwen-VL, Llama 3.2 Vision, and Phi-4 multimodal lines, OpenAI-compatible structured outputs with JSON Schema enforcement during decoding, and tool-calling parity with the OpenAI Chat Completions API, which together eliminate entire classes of retry loops in agentic workflows. Beyond the open-source runtime, Ollama Cloud offers flat-rate monthly tiers, not per-token metering, giving developers access to larger datacenter-class models from US, Europe, and Singapore regions while preserving the exact same local-first developer experience. Ollama integrates directly into tools like Claude Code, Open WebUI, Continue, Cursor, and LangChain, making it the backbone of the local-AI ecosystem for engineers who want privacy, offline capability, and zero per-token cost.