Differences

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--- linux:bash [2026/05/15 13:09] – [ENVIRONMENT VARIABLEs] v1ctor
+++ linux:bash [2026/05/15 13:30] (current) – [REDIRECTS vs PIPES] v1ctor
@@ Line 74: / Line 74: @@
+==== REDIRECTS vs PIPES ====
+The core difference: redirects connect a stream to a file (a redirect always has a file on one side). Pipes connect one process to another process.
+Pipes: process → process:
+<code bash>
+cmd1 | cmd2           # Takes cmd1's stdout and feeds it directly into cmd2's stdin. No file involved
+ls | grep ".txt"      # ls output becomes grep's input
+</code>
 ==== STANDARD INPUT and OUTPUT ====
 Unix programs have 1 input and 2 outputs.
+When you run a command from a terminal, they all go to/from the terminal by default, e.g.:
+<code bash>
+$ cat
+hello   # Stdin is connected to the terminal, you can type there.
+hello   # Stdout - cat prints it right away after you pressed enter.
+</code>
+** < redirects Stdin**
+<code bash>
+cat < foo.txt
+bar
+</code>