Some of the answers here are quite outdated, so I would like to give a new answer.
For help in general
It's always good to ask Slack where to find help for your specific task, because it depends on what you plan to do and what level you are at. Are you, for example, a complete beginner of TYPO3, but a very good programmer? In this case, you need other information from someone who is already familiar with TYPO3, but who starts from scratch as a programmer.
In some cases, the official TYPO3 YouTube video is better for getting started. There is not a single guide or book for TYPO3 developers where you will find everything.
To develop extensions
Print
- Schams / Lobacher: "TYPO3 Extbase: Advanced Extension Design for CMS TYPO3 with Extbase & Fluid"
official documentation
In general, for official documentation, go to https://docs.typo3.org/ and look at the "Links" and "Manuals and Tutorials" pages. Textbooks are best for getting started.
You must select the correct version of TYPO3 that you will use. By default, the "latest" version is loaded. "Last" is the latest development version; it may not be the last LTS. Click "Links" (usually in the lower left corner) and select a version.
Sybille peters
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