If you are using a legacy encoding (ie something without UTF in the name), then there will be characters you may type into your document that Texpad is not able to save to disk. Cannot Save in this encoding errorsДЄpart from incompatibility with modern tools and users, we recommend Unicode encodings as they are the only encodings that are capable of encoding all Characters. In almost all cases this is not a problem, as almost everybody uses UTF-8 in the TeX, and as Texpad is set to this by default, as are recent versions of TeX. This means that Texpad must be set by the user to the correct encoding before opening a file. We wish we could sniff encodings automatically, but this is an imprecise deduction, and the results are catastrophic if Texpad were to guess incorrectly. Sadly, there is no way to deduce the encoding of a file from the file, the information does not exist in the file. We strongly recommend that all users use UTF-8 as their text encoding.

Recent versions of TeX default to UTF-8, as does Texpad. Historically, there are a large number of different ways of encoding text, but current best practices have converged on one of a small number of Unicode encodings (such as UTF-16 and UTF-8) as the best way to do this. This conversion between characters in an editor, and data on disk is known as Text Encoding.

There is a choice on how those characters are converted to data and written to disk. A text document, like a tex source file, consists of a list of characters.

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