This is a problem. Each player is going to have a slightly different personal definition of what constitutes a weakness or a target when we try and put it into English (or whatever your language is). Because we are translating what the brain sees and does when playing into English then we will lose something in the translation. Willy Hendriks writes about the importance of thinking chess and resisting putting it into English in his book Move First, Think Later. His thesis is that you should solve the chess problems and let the brain absorb the patterns you encounter on your diet of chess puzzles. I tend to agree with him and so wouldn't waste too much time nailing down an exact "English" definition when we already have a passable one. Instead do the work to develop your chess language definition by solving problems.
So rather than quibble over a precise definition time is better spent on recognising new patterns so that you are able to identify new targets and weaknesses as your ability improves. At the beginner level this is best served by solving lots of tactical puzzles. In the my daughters school, where I coach, once we think the kids are ready we give them puzzles from the book Winning Chess Tactics For Juniors by Lou Hays. I think this is an excellent book for beginners of all ages. The ones who go through this book a couple of times always increase in strength to about 1400-1500 very rapidly. I thoroughly recommend you get a copy and do the exercises. When you have fnished do them all again. You will find you will have forgotten some and a second or 3rd pass is good to firmly imprint the patterns in your mind. At this point you will have a good pattern recognition for the most common tactical motifs and hence be able to sense and spot the weaknesses and targets based on these themes.
Then read some books on Positional Chess to get a feel for various positional factors. This will further improve your sense of what is weak and strong and so your understanding of the term will develop.
Then keep solving tactical and positional exercises so that you continuously develop. Maybe at this stage Tactics Trainer on chess.com will be very useful but I think that has flaws that help develop bad habits - it has a timer which encourages guessing a solution. This is very bad. There are lots of good puzzle books out there though where you can practice the thinking until it becomes ingrained and at the same time develop your sense of what constitutes a weakness.
I think your understanding of the term "weakness" and "target" will change as you improve and acquire more chess knowledge. This is good because you will still be asking the same questions ingrained in your thinking process but will be identifying finer and finer details in the position as your understanding grows.
This is worth it's weight in gold. I mean it as an expression, not literally, since I don't think bytes weigh much :P, but thank you for this clear ideas and very precise recommendations. It's really encouraging.
I'm going to just type out aronchuck's move-choice rules from memory here, to test myself. 1. what is my opponent's plan? In other words. a. what is my opponent targetting with the move they just made? or b. what did my opponent just do to improve his position which may put him in a position to target something of mine. (I'm not sure about this part b. aronchuck, you can comment on this...). 2. where are the weaknesses, both mine and my opponent's. I assume you do this evaluation after every move of either side? 3. what is my most pooly placed piece and how can I improve it.
We have not discussed 3. poorly placed pieces, but to keep it simple we probably can agree for now that the most elementary understanding of a poorly-placed piece is a piece that is loose, a target, undefended or insufficiently defended. We have also not discussed how to discern weaknesses, but we can go with any of the tactical patterns for now, lined up on the same file or rank, in the range of a knight fork, along the intersection of two diagonals...and we will (or I will) have to learn about pawn weaknesses eventually.
Yes you've pretty much got it.
Q1. Yes what is my opponent's idea? It is not pleasant playing against someone who prevents your ideas. It is the first thing you need to know to be able to prevent them and stop you falling into your opponent's traps.
Q2. Yes you create a list of weaknesses/ targets by asking this one.
One thing I forgot to mention though is that by asking the Questions every move you can build up a working list of weaknesses. Then after your opponent's move he will have either created another weakness to add to your list, repaired a weakness so you can remove it from your list or not done either and so list remains the same. In this way, you only really have to look closely at the last move to see what has changed in order to amend your list and you don't have to search the whole board every time.
Q3. Also improtant - your worst piece is the doing the least amount of work, is far from the action, is blocked by pawns etc. If you have nothing else to do improving this piece will improve your overall position. It is also a piece you are happy to exchange. If it is your opponent's worst piece you want him to keep it so that your counterpart can show its dominance.
yes, makes sense. about 2. Just add/delete from the working list of weaknesses. thanks aronchuck. your three are very easy to remember. and about 3. thank you for clarifying improve worst piece =, far from the action, blocked by pawns, and don't trade a good piece for a bad piece. Interesting, and important. thanks.