> <\body> > This short guide is designed to help you master some of the fundamental notions of . Please move the cursor inside this . You will observe a cyan box that appears around it. On the status bar, at the bottom right of your window, you may also notice the word\Pstrong\Q. These two things reveal part of the of your document. In this case, the bold text was produced using the (also called or ) and the box indicates the scope of thistag. comes with hundreds of tags for different purposes. The tag is used to highlight important pieces of text. Most tags refer to (like highlighting important text) rather than (like printing the characters in boldface). makes use of customizable style files in order to translate intent into layout. This allows you to easily switch to another presentation ( italic instead of bold text) if you change your mind. Tags can be nested. Move the cursor just before the number 2 (for the square) in the formula below and observe that four boxes are displayed : three light grey boxes (one for the entire equation, one for the expression inside the parentheses, and one for the fraction), plus a cyan box for the superscript. The cyan box is always used for the tag with respect to cursor position, and it is called the . <\equation> z=a*|d>|)>. Let us examine more closely the , located at the very bottom of this window, below the editing region. When moving the cursor around in this document, you will notice that the right hand side of the status bar shows the character just before the cursor. Now move the cursor back in the above equation, right after the number 2 and inside the superscript (check that the cyan box is displayed around the number 2). As you see, the status bar lists all englobing environments in order, from the outermost to the innermost one. Experiment by moving the cursor around in the formula while keeping an eye on the status bar. You will soon get comfortable using the feedback from the colored boxes and from the status bar while navigating in documents. There is an invisible character in the formula after the and before the parenthesis in the equation: can you position the cursor and read off what it is from the status bar? You are right, it is an invisible multiplication. In mathematical formulas, you should refrain yourself from using a space if what you really mean is a multiplication. Remember that expects you to write down what you mean, not how it should be displayed. Multiplications should be invisible in the printed version of your document, but you might find it convenient to show them when editing your document. This can be done using the menu . Again position your cursor inside the above equation, and try moving around using the arrow keys . For instance, can you move the cursor from before to to after the and then after the invisible multiplication? Quickly, the cursor movements will probably feel very natural. Remember that the boxes (and in particular the cyan one) indicate where the cursor is located in the document structure. As an exercise, here is a word that uses a different layout for each one of its characters: <\quotation> Experiment adding characters to this word: observe how the exact cursor position determines in which environment a new character gets inserted. Can you insert a second strong letter \<#2018\>c\<#2019\> and asecond lowered letter \<#2018\>z\<#2019\> with only two mouse clicks and two keystrokes? The graphical user interface of is highly context sensitive. In particular, the menus and the toolbars depend on the cursor position. Roughly speaking, the three toolbars serve the following purposes: The first toolbar contains context-independent icons for common operations on files (, , ), common editing operations (, , ) and browsing(, , ). The icons on the second toolbar only depend on the main editing mode (text, mathematics, graphics, etc.). Inside ordinary text, the toolbar is subdivided into the following four groups: <\itemize> the icons , , are used for the insertion of \Plarge environments\Q that structure your document, like sections, theorems, item lists, etc. the icons , , are for common textual markup (emphasis, verbatim, color). the icons , , are specific to the style used by this particular document (they provide acccess to some macros that are useful when writing documentation, and you can ignore them for the moment). the icons , , are for the insertion of special types of markup, such as equations, tables, images, hyperlinks, animations, or interactive sessions. The icons on the third and smallest toolbar are extremely context sensitive. It offers functionalities that are directly connected to the current focus (i.e.the current innermost environment, which is indicated by the cyan box). Observe how the focus bar changes when the cursor is moved; try clicking on the icon when the focus is on the above bullet list (but not immediately after a bullet) and observe what happens. The same mechanism allows displayed formulas to be numbered: go ahead and try it with the ones in this document! It is now time to type your first formula, say <\equation*> f*\x=f-f. Here is how we did it (go ahead and try whether you can repreduce the example): <\itemize> Click on the icon in the mode-dependent icon toolbar to insert a ( alarge centered formula). The integral sign can be found under the icon, available when the cursor is inside aformula. When hovering the mouse over the button with >>, a help balloon allows you to discover the corresponding keyboard shortcut. If you know , then you may also use the command followed by . The subscripts and superscripts can be obtained using the icon in the toolbar, or using the keys and . Make sure you exit the subscript environment before creating a superscript, otherwise you will be creating a superscript inside the subscript: remember that the cyan box is here to help you figure out the exact cursor position. The prime can be inserted directly from the corresponding key . Note that typing an opening parenthesis automatically creates the matching parenthesis as well. To exit the parentheses, use the arrow or . Before the subexpression x>, an invisible multiplication is required: simply use the key. The status bar will confirm that the multiplication sign has been entered correctly. The upright \<#2018\>>\<#2019\> from differential calculus is obtained the shortcut . Here stands for the tab-key and you should press without using the shift key. uses two simple but powerful mechanisms for entering mathematical symbols: <\itemize> Basic symbols can be to obtain more complex ones. For instance, typing > (two successive keystrokes here) yields >. Can you guess how to insert asymbol > before the in the formula below? <\equation*> a=b Such sequences of keystrokes are designed to be intuitive and easy to remember. Guess how to change the formula above to \b>, \b> or even \b>? of a symbol can be obtained using the tab-key , as demonstrated by the differential \<#2018\>>\<#2019\> earlier. When several variants are available, pressing repeatedly cycles through them. In the formula above, type > \ between and , and immediately after this press repeatedly (if you are not sure what a symbol represents, keep an eye on the status bar). This mechanism can be used in particular to obtain Greek letters: try replacing and by > and >, respectively, in the expression of the Lorentz factor from special relativity, <\equation*> g=>>. The two mechanisms can be combined: can you guess how the mathematical symbol > can be obtained? Hint: it is a variant of >. Don't forget entering before trying to insert mathematical symbols or markup. New formulas can be inserted using icon on the mode-dependent icon toolbar or using the keyboard shortcuts (inline formula) or (displayed equation). <\initial> <\collection>