HT-digital is the offline solution for e-books from Verlag Handwerk und Technik.The textbooks can also be used without an active internet connection.Benefits of eBooks:• Can also be used offline• The table of contents is linked so that you can jump directly to the desired chapter/page.• The full-text search for keywords is very convenient. All book locations that contain the search term are displayed as a search result. The pages can be accessed directly with a click.• Desired pages can be reached quickly by entering the page number.• Various functions are offered, such as marking text passages, freehand drawing, inserting comments and annotations, and covering text and images. Thus, the eBooks can be used to design a varied lesson.