diff --git a/README.md b/README.md
index ea5b66a..92939db 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,137 @@
-# navicat-keygen
+# Navicat Keygen
+
+  This repository will tell you how Navicat offline activation works.
+
+## 1. Keyword Explanation.
+
+  * __Navicat Activation Public Key__
+
+    It is a __RSA-2048__ public key that Navicat used to encrypt or decrypt offline activation information.
+
+    It is stored in __navicat.exe__ as a kind of resource called __RCData__. You can see it by a kind of software [___Resource Hacker___](http://www.angusj.com/resourcehacker/). The concrete content is:
+
+    > -----BEGIN PUBLIC KEY-----  
+    > MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAw1dqF3SkCaAAmMzs889I  
+    > qdW9M2dIdh3jG9yPcmLnmJiGpBF4E9VHSMGe8oPAy2kJDmdNt4BcEygvssEfginv  
+    > a5t5jm352UAoDosUJkTXGQhpAWMF4fBmBpO3EedG62rOsqMBgmSdAyxCSPBRJIOF  
+    > R0QgZFbRnU0frj34fiVmgYiLuZSAmIbs8ZxiHPdp1oD4tUpvsFci4QJtYNjNnGU2  
+    > WPH6rvChGl1IRKrxMtqLielsvajUjyrgOC6NmymYMvZNER3htFEtL1eQbCyTfDmt  
+    > YyQ1Wt4Ot12lxf0wVIR5mcGN7XCXJRHOFHSf1gzXWabRSvmt1nrl7sW6cjxljuuQ  
+    > awIDAQAB  
+    > -----END PUBLIC KEY-----  
+
+    If you have the corresponding private key, please tell me. I would be very appreciated for your generous.
+
+  * __Request Code__
+
+    It is a Base64 string that represents 256-bytes-long data, while the 256-bytes-long data is the cipher text of the __offline activation information__ encrypted by __Navicat Activation Public Key__.
+
+  * __Offline Activation Request Information__
+
+    It is just a JSON-style ASCII string which contains 3 items. Respectively they are `"K"`, `"DI"` and `"P"`, which represent __snKey__, __checksum__ (related with your machine and OS), __Platform__ (Appropriately speaking, it should be OS Type).
+
+    Like:  
+    > {"K": "xxxxxxxxxxxxxxxx", "DI": "yyyyyyyyyyyyy", "P": "WIN8"}
+
+  * __Activation Code__
+
+    It is a Base64 string that represents 256-bytes-long data, while the 256-bytes-long data is the cipher text of the __offline activation response information__ encrypted by __Navicat Activation Private Key__ (so far, we don't know official activation private key).
+
+  * __Offline Activation Response Information__
+
+    Just like __Offline Activation Request Information__, it is also a JSON-style ASCII string. But it contains 5 items. Respectively they are `"K"`, `"N"`, `"O"`, `"T"`, '`DI`'.
+
+    `"K"` and `"DI"` has the same meaning mentioned in __Offline Activation Request Information__ and must be same with the corresponding items in __Offline Activation Request Information__.
+
+    `"N"`, `"O"`, `"T"` represent __Name__, __Organization__, __Time__ respectively. __Name__ and __Organization__ are string and the type of __Time__ is unknown.
+
+    `"T"` can be omitted.
+
+  * __snKey__
+
+    It is a 4-block-long string, while every block is 4-chars-long.
+
+    __snKey__ is generated by 10-bytes-long data. In order to explain it easily, I use __data[10]__ to represent the 10-bytes-long data.
+
+    1. __data[0]__ and __data[1]__ must be `0x68` and `0x2A` respectively.
+
+       _`May change when Navicat product changes. Uncertain yet.`_  
+
+    2. __data[2]__, __data[3]__ and __data[4]__ can be any byte. Just set them whatever you want.
+
+       _`May change when Navicat product changes. Uncertain yet. But it's very possible right.`_  
+
+    3. __data[5]__ and __data[6]__ must be `0xCE` and `0x32` respectively.
+
+       _`May change when Navicat product changes. Uncertain yet.`_  
+
+    4. __data[7]__ represents whether it is __commercial license__ or __non-commercial license__.
+
+       In Navicat 12: `0x65` is __commercial license__, `0x66` is __non-commercial license__.  
+       In Navicat 11: `0x15` is __commercial license__, `0x16` is __non-commercial license__.  
+
+       _`May change when Navicat product changes. Uncertain yet.`_  
+       _`Must change when version change.`_  
+
+    5. High 4 bits of __data[8]__ represents __version number__. Low 4 bits is unknown, but we can use it to delay activation deadline. Possible value is `0000` or `0001`.
+
+       In Navicat 12: High 4 bits must be `1100`, which is the binary of number `12`.
+       In Navicat 11: High 4 bits must be `1011`, which is the binary of number `11`.
+
+       _`Must change when version change.`_  
+
+    6. __data[9]__ is unknown, but you can set it `0xFD` or `0xFC` or `0xFB` if you want to use __not-for-resale license__.
+
+       _`May change when Navicat product changes. Uncertain yet.`_  
+
+    After that. Navicat use __DES__ with __ECB mode__ to encrypt the last 8 bytes which are from __data[2]__ to __data[9]__.
+
+    The DES key is:
+
+    ```cpp
+    unsigned char DESKey = { 0x64, 0xAD, 0xF3, 0x2F, 0xAE, 0xF2, 0x1A, 0x27 };
+    ```
+
+    Then encode the 10-bytes-long data:
+
+    1. Regard __data[10]__ as a 80-bits-long data.
+
+       If __data[10]__ starts with `0x68` and `0x2A`, so the 80-bits-long data is `01011000 00101010......`
+
+    2. Divide the 80-bits-long data as 16 5-bits-long blocks.
+
+       If __data[10]__ starts with `0x68` and `0x2A`, so the 80-bits-long data is `01011`, `00000`, `10101`, `0....`, ...
+
+    3. So the value every block is less than 32. Map them by a encode-table:
+
+       ```cpp
+       char EncodeTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567";
+       ```
+
+       Then you will get a 16-char-long string.
+
+       If __data[10]__ starts with `0x68` and `0x2A`, so after encoded, it should starts with `"N"`, `"A"`, `"V"`.
+
+    4. Divide the 16-char-long string to four 4-chars-long blocks, Then you get __snKey__.
+
+## 3. Activation Process
+
+  1. Check whether __sn_Key__ that user inputs is legal.
+
+  2. After user clicks `Activate`, Navicat will start online activation first. If fails, user can choose offline activation.
+
+  3. Navicat will use the __snKey__ that user inputs and some information collected from user's machine to generate __Offline Activation Request Information__, then encrypt it by __Navicat Activation Public Key__ and return Base64-encoded string as __Request Code__.
+
+  4. In legal way, the __Request Code__ should be sent to Navicat official activation server by a Internet-accessible computer. And Navicat official activation server will return a legal __Activation Code__.
+
+     But now, we use keygen to play the official activation server's role.
+
+     1. According to the __Request Code__, Get `"DI"` value and `"K"` value.
+
+     2. Fill __Offline Activation Response Information__ with `"K"` value, name, organization name and `"DI"` value.
+
+     3. Encrypt __Offline Activation Response Information__ by __Navicat Activation Private Key__ and you will get 256-byte-long data.
+
+     4. Encode 256-byte-long data by Base64. The result is __Activation Code__.
+
+  5. Input __Activation Code__, then offline activation is done.