Answers.Body: <p>The usage of the word "control" in chess actually does fit its <a href="https://www.merriam-webster.com/dictionary/control" rel="noreferrer">lexical definition</a> pretty well:</p>
  
  <blockquote>
    <p><strong>to exercise restraining or directing influence</strong> </p>
  </blockquote>
  
  <p>If the rook on e1 in your example restrains the opponent's pieces to occupy squares on that file, he does have this influence. </p>
  
  <p>At the same time, since he can't move very far, these pieces do have "control" of (most of) the e-file <em>at the same time</em>. </p>
  
  <p>"Control" is <em>not</em> binary, and you might have been confused by the assumption that it is. Between full white control and full black control of a square, there are many shades in between. E.g., in your example, both sides have some "control" over the e-file. They can't advance first, but they can punish the other side if it does. There are other cases where the control is more absolute and the controlling side can occupy the controlled squares whenever it wants to.</p>
  
  <p>A piece doesn't even need to be able to occupy a square in its next move to exercise "control" over it! For example, a fianchettoed bishop often has some form of control over its diagonal, even while a friendly knight still sits in his way (because there always is the threat of it moving away). Or, in your example, the rook may still "control" the e-file with a white bishop on e2 (to a lesser degree. It mostly restrains the black queen).</p>
  
  <p>Another form of "control" is by bodyblocking the opponent's pieces from reaching some square(s). This is often meant in sentences like "White's last pawn move allows him to control more space" - the actual number of squares the pawn can control <em>directly</em> is fixed(2), but it now might also restrain the opponent from occupying the squares behind it (depends on the context). </p>
  
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Answers.CreationDate: 2017-09-20T13:13:54.900Z
Answers.LastActivityDate: 2017-09-20T13:37:26.893Z
Answers.LastEditDate: 2017-09-20T13:37:26.893Z
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Body: <p>One of the important factors to take into account is 'control' of squares, ranks, files and diagonals. But what exactly, does it mean when we say that a player 'controls' space? </p>
  
  <p>The reason I ask is that many, many times, I have seen commentators say 'white plays Re1 to control the open e-file'. I was looking at a game some time ago, and sure enough, this comment was made. But when I looked at the postion, the only other square that the rook could occupy WITHOUT BEING CAPTURED was e2. It couldn't occupy any other square along that file, all of which were covered by black. So, how can you say that the rook was 'controlling' the e-file? </p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2017-09-22T22:16:17.260Z
Comments.Text: In your example White does not have undisputed control.  But he does influence the e-file with the rook and in that way controls it.  Black would not want to put his queen on the e-file now, for example.
Comments.UserDisplayName: Ywapom
Tags: <strategy>
Title: What is 'control?'
ThreadText: # What is 'control?'
  
  (Asked by: username_0 on 2017-09-20)
  
  One of the important factors to take into account is 'control' of squares, ranks, files and diagonals. But what exactly, does it mean when we say that a player 'controls' space?
  
  The reason I ask is that many, many times, I have seen commentators say 'white plays Re1 to control the open e-file'. I was looking at a game some time ago, and sure enough, this comment was made. But when I looked at the postion, the only other square that the rook could occupy WITHOUT BEING CAPTURED was e2. It couldn't occupy any other square along that file, all of which were covered by black. So, how can you say that the rook was 'controlling' the e-file?
  
  **Tags:** strategy
  
  > **Comments:**
  > **username_1**: In your example White does not have undisputed control.  But he does influence the e-file with the rook and in that way controls it.  Black would not want to put his queen on the e-file now, for example.  
  
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  ## 1 answers
  
  ### Answer by username_2 on 2017-09-20. Score: 8
  
  The usage of the word "control" in chess actually does fit its [lexical definition](https://www.merriam-webster.com/dictionary/control) pretty well:
  
  > **to exercise restraining or directing influence**
  
  If the rook on e1 in your example restrains the opponent's pieces to occupy squares on that file, he does have this influence.
  
  At the same time, since he can't move very far, these pieces do have "control" of (most of) the e-file *at the same time*.
  
  "Control" is *not* binary, and you might have been confused by the assumption that it is. Between full white control and full black control of a square, there are many shades in between. E.g., in your example, both sides have some "control" over the e-file. They can't advance first, but they can punish the other side if it does. There are other cases where the control is more absolute and the controlling side can occupy the controlled squares whenever it wants to.
  
  A piece doesn't even need to be able to occupy a square in its next move to exercise "control" over it! For example, a fianchettoed bishop often has some form of control over its diagonal, even while a friendly knight still sits in his way (because there always is the threat of it moving away). Or, in your example, the rook may still "control" the e-file with a white bishop on e2 (to a lesser degree. It mostly restrains the black queen).
  
  Another form of "control" is by bodyblocking the opponent's pieces from reaching some square(s). This is often meant in sentences like "White's last pawn move allows him to control more space" - the actual number of squares the pawn can control *directly* is fixed(2), but it now might also restrain the opponent from occupying the squares behind it (depends on the context).
  
  
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