Whitespace characters, whitespaces, spaces
Blank (SP), horizontal (HT) and vertical tabulation (VT), a symbol of a new line (LF) and carriage return (CR). These symbols are not represented in any way on the screen, but influence position of symbols following them.
Non-whitespaces, non-spaces
These are letters, figures, punctuation symbols – everything that is evidently represented on the screen or paper.
Group of the non-whitespace symbols divided by whitespaces. In a word is not present whitespaces. Specifics of the term "word" in TextLab documentaion context:
  • The punctuation marks adjoining by the way, are considered as a part of this "word" and at the further transformations of the text do not separate from a word.
  • Symbols in quoted phrases (in string literals in programming languages) are ignored at text breakdown on words. Whole quoted a phrase is considered as one "word".
  • In program source code, in comments in the end of lines whitespaces are ignored at text breakdown on words. Whole comment is considered as one "word".

In other words, "word" in TextLab context is any indivisible in the course of transformations of the text sequence of symbols. TextLab leaves these indivisible sequences in inviolability (except for the operations which are carried out at level of symbols, code conversions and register change).

Отступ (Indent)
Часть строки от её начала до первого изображаемого слова. Отступ может содержать пробелы или символы табуляции. При вычислении размера отступа учитывается размер табуляции, выраженный в символах пробела.
Text part between two symbols of a new line (LF, line feed).

In context TextLab differs three parts of a line:

  • Indent;
  • Significant part;
  • End line Comment.
Significant part of line
Part of a line, since the first non-whitespaces symbol, and till the end of a line or till the comment in the end of a line. Program source code, in a significant part of a line it is not accepted to use tabulation symbols. The significant part of a line can contain aligning spaces.
End line comment
Many programming languages support possibility to insert the comment in the end of a line, separating the comment from a significant part of a line by special sequence of symbols (// for С/C ++/C #, - for T-SQL). The comment in the end of a line is not exposed to transformations at performance of operations TextLab and is considered as one "word".
The part of the text divided from other text by the empty lines. The line containing only whitespaces is considered in this case empty.
Aligning spaces
The blanks added in a significant part of a line, for moving of its words across. Words move across for the coordination of their position with similar words on sense on the next lines (for creation of effect of columns).
Tab saved spaces
Blanks, as a part of indent of a line which can be replaced with a tabulation symbol.