GoKawiilChatGPT was probably most people's first encounter with an LLM, considering how many users it picked up shortly after its launch in 2022. It also enjoyed the privileged position of having no real competition until Anthropic released Claude a few months later in March 2023. Since then, both companies have constantly improved their models and added new features. But because there's an overlap in features — both platforms have a coding mode and a dedicated workspace mode — it can be difficult to decide which tool is best for you.
Also, there's little difference between the two during everyday usage: You can use either of them to code, answer a quick query, summarize documents, organize your files, and, if you're feeling particularly blasphemous, write thought leadership pieces in the style of Herman Melville.
However, anything beyond that, and you'll need to start thinking about which LLM fits your use case better.