What are Line and Word Wrapping?
By default, most text editors display text without wrapping. That is, lines are endless (or very nearly so) until you hit Enter and start a new line. Line wrapping is a display preference in most text editors that will wrap (or break) lines when they reach a certain length. The wrapping does not affect the line itself, but only how it is displayed to you. Any wrapped line is still treated as one line for all functional purposes, but is displayed as two or more lines in your text editor.
Word wrapping is a supplementary feature to line wrapping that will wrap lines between words rather than in the middle of words. Again, this is a readability feature rather than one that affects the text itself. Word wrapping is usually included in the same function as line wrapping.
Line and word wrapping are useful if you want to be able to see all of the text from a line without scrolling horizontally, or if you're writing plain text articles and don't want your paragraphs to go on sideways forever. Conversely, not wrapping lines is important when you need to be able to view the actual structure of what you're writing, like how many lines are in your document, for example.
Even very basic text editors, like the default Windows Notepad, include word wrapping functions. However, more advanced text editors often include more customizable wrapping options. For example, you can choose whether to wrap by number of characters, by window, or by page. You can also specify certain words that should or should not be wrapped, among other options.
Whether or not you need to worry about wrapping depends on what you're using your text editor for. For most basic text editing operations, Notepad's simple Wrap/No Wrap option should be sufficient. However, more serious users should definitely consider choosing a text editor with more customizable choices.