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+## How Metrics Work
+
+Every executable file in this directory is a calculator of a few
+metrics. They all are expected to be executed like this:
+
+```bash
+./cloc.sh Foo.java log.txt
+```
+
+Here, `Foo.java` is the path of the Java file to examine and
+`log.txt` is the path of the file where the output is supposed
+to be saved.
+
+It is expected, that the `log.txt` will contain the following
+text after the script finished successfully:
+
+```
+NoBL 42 Number of Blank Lines
+NoCL 44 Number of Commenting Lines
+LoC 323 Total physical lines of source code
+```
+
+There are three columns in the file. The first one should contain
+the name of the metric. The second one contains the value (float or integer).
+The third one contains the description of the metric (in general, NOT
+for this particular file). A space is mandatory between the first and the
+second column, and between the second and the third columns.