diff --git a/knowledge base/sort.md b/knowledge base/sort.md
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+# Sort
+
+## TL;DR
+
+```shell
+# Sort all given lines.
+sort path/to/file
+
+# Sort all lines reverse.
+sort -r path/to/file
+
+# Sort lines numerically.
+sort -n path/to/file
+
+# Sort lines and remove duplicates.
+sort -u path/to/file
+```
diff --git a/knowledge base/uniq.md b/knowledge base/uniq.md
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+# Uniq
+
+## TL;DR
+
+```shell
+# Print all but duplicates lines.
+uniq path/to/file
+
+# Only print unique lines.
+uniq -u path/to/file
+
+# Only print repeating lines.
+uniq -d path/to/file
+
+# Count unique lines only.
+uniq -cu path/to/file
+
+# Count duplicated lines only.
+uniq -cd path/to/file
+```