There are all sorts of "obvious" things that people don't think of teaching beginners when they introduce them to computers. Well, they often aren't at all obvious to the poor learner. I'm going to try to give you a guide to some important "obvious" things which often pass people by, but bear in mind that I'm assuming you are using a PC rather than a Mac.
Lesson 1: let's begin by looking at how to use the mouse or trackpad. If you are using a laptop computer it will probably have a trackpad set in front of the keyboard: by dragging your finger over the surface of the trackpad you can make a "cursor" move about the screen. If you don't have a trackpad, you will need to use a rodent instead: hold the rodent down against a flat surface and drag it about from side to side to make the cursor move. If it squeeks loudly, try another rodent. Some rodents have tails which need to be plugged into the computer, but never plug in or unplug a rodent while the computer is switched on unless the plug is a USB plug: you'd better ask someone if you're not sure. The trackpad or rodent will have at least two buttons on it. If it has three, then ignore the middle one. Normally when you are told to click on something, it means you have to line the cursor up with something on the screen that you want to click on, and then you click the left button on the trackpad or rodent. Tip: you can tell if you are holding the rodent the right way round because the cursor should move across the screen to the left when you drag the rodent to the left.
Lesson 2: this page is being displayed to you within a "window", and the top right corner of a window usually has three "buttons" in it, as shown in the picture above. The one right in the corner is a cross, and if you were to line up the cursor on top of the cross and then click on it - BUT DON'T DO IT NOW - you would close the window, and that means the whole window displaying this page would disappear from sight, and the program would close as well, making it difficult for you to find your way back here. The button next to the one with the cross is a slightly safer one to click on, but I wouldn't advise it until after you've read the rest of this and the next paragraph: it will either make the window bigger or smaller. If it becomes smaller, you can make the window bigger again by clicking on the same button, but BEWARE: when the window changes size it will move the corner with it, so it might expose another window behind the one you're working with, and the corner of that window will look the same as the one that's just moved away from there. You want to make sure you are clicking on the button for this window rather than a bigger window behind it, so it's the second button in from the top right corner of this window that you want to click on.
indentThe third button in from the top right corner does much the same thing again, only instead of making the window smaller, it hides it almost completely: the window actually shoots down to the bottom of the screen and becomes a little "tab". This is know as minimising. To make the window appear again, you need to click on that tab at the bottom of the screen. Now that you know this, it should be safe for you to click the two buttons next to the cross because you will know how to undo them, but you'll still want to avoid clicking on the cross - you're probably reading this page by using a program to display it called a "browser", and you're probably also connected to the Internet (because that's where this page comes from), so it's important that you avoid clicking on the cross until you actually want to get off the Internet. If you do click it by mistake, you might not know how to find your way back here, and you'd need to get more help from whoever brought you here in the first place.
Lesson 3: On the bottom row of keys on the keyboard there is usually a key with a windows logo on it (a fluttering flag, probably next to an Alt key). Pressing it does nothing, but when you release it the start menu will appear. The start menu is the route to a whole bunch of things that you might need to get into, whether you want to look for a file on the hard drive or to open and run another program. However, the normal way to start up your favourite programs is to double-click on a symbol on the main screen, called the desktop. To get to the desktop quickly, you can minimise all open windows in one go just by holding down the windows key (next to the Alt key) and pressing the M key. Any open windows will immediately shoot down into their tabs at the bottom of the screen, saving you from clicking on the "minimise" button of each open window. You can then start up a program by clicking on its symbol, and you can then go back to whatever you were doing before by clicking on one of the tabs at the bottom of the screen. When you are running more than one program at the same time, you can also jump in and out of the different programs by clicking on their tabs at the bottom of the screen.
Starting up a program from the start menu is not as easy as double-clicking on symbols on the desktop: you have to hunt through a long list of programs, and as you move the cursor around, lists of still more programs appear and disappear wildly, and it's quite hard to move the cursor into the list you're after without it vanishing: you'll often find yourself in the wrong list instead and have to backtrack. Have a go now and see what I mean (if you get lost while trying to follow the following instructions, just press the "Esc" key in the top left corner of the keyboard a couple of times and you'll come back here - you should probably write out the instructions before you start because the menus that appear will cover them on the screen). Begin by pressing (and releasing) the window key (next to the Alt key) to make the start menu appear; then put the cursor on top of "All Programs". When the lists appear, try to move the cursor onto "Accessories", then when the Accessories list appears try to move the cursor onto "Notepad". It's not at all easy! Fortunately, there is an easier way: begin by pressing the window key as before; then press P. You may have to press P more than once, but your aim is to get the bit saying "All Programs" to be highlighted. Once it is highlighted, press the return key (the big key with a bent arrow on it at the right hand end of the main part of the keyboard. A list of programs should appear. Press A (more than once if necessary until "Accessories" is highlighted, and then press the return key (bent arrow key). Another list should appear. Press N until "Notepad" is highlighted, and then press the return key (if you need to, because pressing N might take you straight into Notepad if there's no other program in the list starting with the same letter). Now isn't that much easier than trying to do things by mouse or trackpad! You can then close Notepad by clicking on the cross in the top right corner of its window.
Lesson 4: Highlighting text is an important skill. There are two ways of doing it. The easiest method is to use one of the shift keys along with the cursor keys, though it won't work at all when you're reading a Web page like this one, so you'll need to try this out in a word processor or text editor document. Your computer may not have a proper word processor on it, so your best bet is to open the text editor called Notepad (follow the instructions in the previous paragraph. Once you are into Notepad, write a little bit of text to do some experiments with (it can be complete gibberish if you like). You may need to click on "format" at the top of the window and then "word wrap" to stop your text disappearing off the right-hand side of the window. Okay, so now to the business of highlighting text: the shift keys, if you don't know what they are, are the ones used to turn small letters into capital letters: they probably have an upward-pointing arrow printed on them, but you'll find them easily enough by looking two places to the left of the Z key and several places to the right of the M key. The cursor keys are a cluster of four arrow keys, one pointing up, one down, one left, and one right. You can use the cursor keys to move the cursor around the piece of text that you have written. If you hold down a shift key and then press the cursor keys, you will see for yourself how they can be used to highlight text. Notice also that there are two cursors: the main cursor which is moved around using the cursor keys, and the trackpad/rodent cursor which doesn't interfere with what you're doing unless you click (in which case the main cursor will try to jump to the point within the text zone as close as it can get to the trackpad/rodent cursor, but at the same height on the screen). Many trackpads take being tapped as a click, so you may find the main cursor keeps being stolen away from you as you type: this is extremely irritating, so if you plan to do a lot of writing you would do well to buy a separate USB keyboard to plug in. Alternatively you could plug in a rodent to use instead of the trackpad, and then disable the trackpad, but on some machines it can be hard to find the route to turning it off.
indentOnce you have highlighted a bit of text, what can you do with it? Well, you can delete it by pressing either of the delete keys (the delete-right key actually says "Delete" on it, but the delete-left key (also known as the backspace key, for that's what it was on old typewriters) usually has a long arrow on it pointing to the left. Highlighted text will in fact be deleted if you press a letter key too, and that letter will replace it. It's easy to make a mistake and delete highlighted text when you don't intend to, but if this happens you should not panic: just take your hands off the keyboard and stop to think. If you click on "edit" at the top of the window, it will give you the option "undo", but this option is only available so long as you haven't either deleted anything else or haven't moved the cursor and typed anything else since you accidentally deleted the highlighted text. Holding down the Alt key and pressing the delete-left key is another way of doing "undo", as is holding down the CTRL key and typing Z, but you may not remember either of these in the heat of the moment, so it's safest to take a moment to think, then click on "edit", and then click on "undo".
indentYou can also copy highlighted text by holding down one of the Ctrl keys (some machines only have one Ctrl key) and typing C (Ctrl + C). You can then de-highlight the text by pressing a cursor key, perhaps move the cursor key to the end of the text you've written, and then hold down the Ctrl key and type V (Ctrl + V) to paste the copied text into the document. You can paste it again and again if you like. If you use Ctrl + X instead of Ctrl + C, it will copy the highlighted text and delete it at the same time (ie. copy and cut). You can then past it back in using Ctrl + V. It is well worth practising using these copy, copy and cut, and paste functions because they are the easiest way to move text from one document to another. You can copy text from a browser window too (like the one you're reading from right now), but unfortunately the method of using a shift key and cursor keys to highlight text won't work with the browser, so you need to use a different method for highlighting text. Put the trackpad/rodent cursor at the start of the bit of text you want to copy, then press and hold down the left button of the trackpad/rodent, then drag your finger along or down the trackpad or drag the rodent along or downwards, and when the end of the highlighted bit reaches the point you want, you let go of the button. It's fiddly, and it takes a bit of practising to get the hang of it, but once you've managed to highlight a bit of text this way, you can copy it using Ctrl + C as before, and then you can paste it into your Notepad document with Ctrl + V. You would do well to make a note of all these things on a piece of card: Window-key + M (minimises all windows), Ctrl + X (copy and cut), Ctrl + C (copy without cutting), Ctrl + V (paste), Ctrl + Z (undo).
Lesson 5: Progress bars. The picture above shows at its right-hand edge a long, very thin vertical box called a progress bar: it has an up button at the top and a down button at the bottom which you can use to navigate your way to stuff that's off the top or bottom of the screen. You can see another progress bar like it at the right-hand edge of the screen or of this window, if the window doesn't fill the screen. There is also a button in the space somewhere between the up and down buttons, and the size of this button indicates the size of the displayed content of the window relative to the amount of stuff off the top and bottom of the screen. If you click on this middle button and hold the clicker down, you can then drag the button up and down to get to the content off the top or bottom of the screen more quickly. Alternatively, you can click in the space over or under this middle button to make it jump up or down to jump quickly through a document.
Lesson 6: The screen-grab. There is a key which says "Prt Sc" on it, and this obviously stands for "print screen". Pressing it appears to do nothing, but it actually copies the screen into a hidden location rather than printing it. To save this copy of the screen, you'll need to paste it into a file somewhere. The easiest way to do this is to open a program called Paint which you can find in the Accessories list along with Notepad. Open it up and then do Ctrl + V to paste the screen-grab into it. You can now save it by clicking on "file" near the top left of the screen, followed by "save as". You will then see a window with the following at the bottom of it:-
You type the name you want to give the file into the top of these boxes, then you can change the content of the second box by clicking on the arrow at its right-hand end: JPEG is usually the best one to choose as it results in a small file size without losing much detail. Click the "save" button (on the screen) to complete the process. The file should be saved into a folder called "My Pictures", and you can find it via the start menu: it should be saved in there in such a way that it looks and behaves like an ordinary photo file. Doing a screen-grab is sometimes the only way to save something you see on a Web page, so it's worth learning how to do it properly. If you don't want to save the whole screen as a picture file, it is easy enough to select part of it once you have pasted the whole screen-grab into Paint.
You need to click on the symbol highlighted in the above picture (the rectangle with a dashed edge, next to the star and under the word "edit"). This turns the cursor into a select tool. You now place the cursor (using rodent or trackpad) at one corner of the part of the image you want to select, click and hold down the left clicker on your rodent or trackpad, then drag the cursor to the opposite corner of the part you want to select and let go of the clicker when the cursor's in the right place. You should then end up with a dotted line round a rectangle, the part of the screen you actually want to save as a picture. You now want to save this and paste it into an empty Paint program, and you can do so as follows: Ctrl + C (to copy the selected area), Ctrl + N (to clear everything out of Paint), Press N on its own (to say that you don't want to save the changes), and then press Ctrl + V (to paste back in the selected area on its own). Now save the picture in the usual way ("file", then "save as", etc.).
One last trick with this: if you want to save really small bits of the screen, you need to reduce the size of the white area that you are offered by Paint, because if your image is smaller than that it will be saved with white sticking out from one side and/or under it. To do this, click on "image", then "attributes..." and you will be able to change the size of the white area: changing each number to 50 will probably be sufficient.
Lesson 7: ...
To be continued later, but I hope the above helps you in the meantime.
(List of possible topics to add: saving files; copying files to other places; organising your files into folders; ...)