diff --git a/Cryptography/README.md b/Cryptography/README.md
index a802ce5..3e1f9a2 100644
--- a/Cryptography/README.md
+++ b/Cryptography/README.md
@@ -1,3 +1,27 @@
 # TOOLS:
 
-- https://www.cryptool.org/en/cryptool1-en
\ No newline at end of file
+- https://www.cryptool.org/en/cryptool1-en
+
+- frequency analyses online: 
+
+
+## ROT13
+
+In the command line
+```
+VAR=$(cat data.txt)
+echo "$VAR"
+alias rot13="tr A-Za-z N-ZA-Mn-za-m"
+echo "$VAR" | rot13
+```
+----
+
+
+In Python we can use: ```"YRIRY GJB CNFFJBEQ EBGGRA".decode(encoding="ROT13")```
+https://docs.python.org/2/library/codecs.html#codec-base-classes
+
+---
+
+Online: 
+
+http://www.xarg.org/tools/caesar-cipher/
diff --git a/Cryptography/ROT_13_EASY.md~ b/Cryptography/ROT_13_EASY.md~
deleted file mode 100644
index 94f3727..0000000
--- a/Cryptography/ROT_13_EASY.md~
+++ /dev/null
@@ -1,10 +0,0 @@
-```
-VAR=$(cat data.txt)
-echo "$VAR"
-alias rot13="tr A-Za-z N-ZA-Mn-za-m"
-echo "$VAR" | rot13
-```
-
-
-In Python we can use: ```"YRIRY GJB CNFFJBEQ EBGGRA".decode(encoding="ROT13")```
-https://docs.python.org/2/library/codecs.html#codec-base-classes
diff --git a/Cryptography/ROT_13_EASY.md b/Cryptography/RotationCiphers/ROT_13_EASY.md
similarity index 100%
rename from Cryptography/ROT_13_EASY.md
rename to Cryptography/RotationCiphers/ROT_13_EASY.md
diff --git a/Cryptography/RotationCiphers/brute_force_rotation.py b/Cryptography/RotationCiphers/brute_force_rotation.py
new file mode 100644
index 0000000..155ef43
--- /dev/null
+++ b/Cryptography/RotationCiphers/brute_force_rotation.py
@@ -0,0 +1,17 @@
+#!/usr/bin/python
+import sys
+
+CIPHER = "OMQEMDUEQMEK"
+LETTERS = list("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
+CIPHER = ""
+shift = 1
+
+while i < len(LETTERS):
+ for c in CIPHER:
+  if c in LETTERS:
+   CIPHER += LETTERS[(LETTERS.index(c)+shift)%(len(LETTERS))]
+ print("Shift used: " + str(shift))
+ print("Ciphertext: " + CIPHER)
+ print("CIPHER: " + CIPHER)
+ shift = shift + 1
+ CIPHER = ""
diff --git a/Reverse_Engineering/COMMAND_LINE_TOOLS.md b/Reverse_Engineering/COMMAND_LINE_TOOLS.md
new file mode 100644
index 0000000..890ff54
--- /dev/null
+++ b/Reverse_Engineering/COMMAND_LINE_TOOLS.md
@@ -0,0 +1,68 @@
+COMMAND LINE TOOLS
+==================
+
+
+### Tricks:
+
+- Files with spaces in the name + symbolinc links.
+
+
+### Searching
+
+
+```
+grep word f1
+
+sort | uniq -c
+
+diff f1 f2
+
+find -size f1
+```
+
+
+### Encondings/ Binaries
+
+```
+file f1
+
+ltrace bin
+
+strings f1
+
+base64 -d
+
+xxd -r
+```
+
+
+
+### Compressed Files
+
+
+```
+zcat f1 > f2
+
+gzip -d file
+
+bzip2 -d f1
+
+tar -xvf file
+```
+
+
+
+### Connecting to a Server/Port
+
+```
+echo 4wcYUJFw0k0XLShlDzztnTBHiqxU3b3e | nc localhost 30000
+
+openssl s_client -connect localhost:30001 -quiet
+
+nmap -p 31000-32000 localhost
+
+telnet localhost 3000
+```
+
+
+