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 # Vim Vixen
 
-An Firefox add-ons works with WebExtensions, insipired by [Vimperator](https://github.com/vimperator).
-
-## Background
-
-### Firefox will stop supporting legacy add-ons
-
-Firefox will support only add-ons using WebExtensions API since version 57, and
-plugins based on legacy APIs will be unavailable.  Vim Vixen is new solution to
-create Vim-like Firefox.
-
-### Vimimum
-
-[Vimium](https://github.com/philc/vimium) is a Chrome extension which able to
-navigate pages in Google Chrome/Chromium.  Vimium also started to suppprt on
-Firefox by WebExtensions API.
-
-## TODO
-
-- [ ] open command
-  - [x] open a link
-  - [x] search by keywords with engined
-  - [x] complete URLs from history
-  - [ ] complete keywords for search
-- [x] tabs navigation
-  - [x] select a tabs by keyboard
-  - [x] close/reopen a tab
-  - [x] reload a page
-- [ ] buffer control
-  - [x] select a tab by :buffer command
-  - [x] buffer completion
-  - [ ] list buffers
-  - [ ] select buffer last selected
-- [ ] discover a content
-  - [x] scroll a page by keyboard
-  - [x] zoom-in/zoom-out
-  - [ ] find a keyword in the page
-- [ ] navigations
-  - [ ] yank/paste page
-  - [x] pagenation
-  - [x] open parent page
-  - [x] open root page
-- [ ] hints
-  - [x] open a link
-  - [x] open a link in new tab
-  - [x] activate input form
-- [ ] misc
-  - [x] configurable keymaps
-  - [x] search engine settings
-  - [x] .rc file
-  - [ ] other commands in Ex mode
-- [ ] supporting Google Chrome/Chromium
+Vim Vixen is a Firefox add-on which allows you to navigate with keyboard on the browser.
+Firefox started to support WebExtensions API and will stop supporting add-ons using legacy APIs from version 57.
+For this reason, many legacy add-ons do not work on Firefox 57.
+and Vim Vixen is a new choise for Vim users since Vim Vixen uses WebExtensions API
+
+## Basic usage
+
+### Key-maps
+
+The key-maps are configurable in preferences of the add-ons.
+The default mapping are shown in the following.
+
+#### Console
+
+- `:`: open console
+- `o`,`t`,`w`: open a page in current tab, new tab, or new window
+- `O`,`T`,`W`: similar to `o`,`t`,`w`, but that contains current URL
+- `b`: Select tabs by URL or title
+
+#### Scrolling
+
+- `k`,`k`: scroll vertically
+- `h`,`l`: scroll horizontally
+- `<C-U>`,`<C-D>`: scroll pages by half of screen
+- `<C-B>`,`<C-F>`: scroll pages by a screen
+- `0`,`$`: scroll a page to leftmost/rightmost
+- `gg`,`G`: scroll to top/bottom
+
+#### Tabs
+- `d`: delete current tab
+- `u`: reopen close tab
+- `K`/`J`: select prev/next tab
+- `r`: reload current tab
+- `R`: reload current tab without cache
+
+### Navigation
+- `f`: start following links in the page
+- `H`: go back in histories
+- `L`: go forward in histories
+- `[[`,`]]`: find  prev/next links and open it
+- `gu`: go to parent directory
+- `gU`: go to root directory
+
+#### Misc
+- `zi`,`zo`: zoom-in/zoom-out
+- `zz`: Set default zoom level
+- `y`: copy URL in current tab
+
+### Console commands
+
+Vim-Vixen provides a console likes Vimperator's one.
+The console is opened by `:` key or keys to open console with initial value
+likes `o`, `t`, or `w` keys.
+
+#### `:open` command
+
+Open a URL or search keywords by search engine in current tab, 
+When specified parameter is formatted in URL as following, URL is opened to current tab.
+
+```
+:open http://github.com/ueokande
+```
+
+If specified parameters are keywords as following, open new tab searched by the
+keywords with search engines (default to Google).
+
+```
+:open How to contribute to Vim-Vixen
+```
+
+You can specify search engines in first parameter.
+For the default of search engines, see [search engines](#search-engines) section.
+
+```
+:open yahoo How to contribute to Vim-Vixen
+```
+
+
+#### `:tabopen` command
+
+Open a URL or search keywords by search engine in new tab.
+
+#### `:winopen` command
+
+Open a URL or search keywords by search engine in new window.
+
+#### `:buffer` command
+
+Select tabs by URL or title matched by keywords.
+
+### Search engines
+
+Vim-Vixen support to search by search engines such as google or yahoo.
+But the engines are independent on browsers' because of there is a limitation of WebExtensions.
+
+You can configure search engines and default search engine in preferences of the add-ons.
+The URLs specified in `"engines"` must contain a {}-placeholder, which will
+replaced with keywords in parameters of the command.
+
+```json
+{
+  "keymaps": {
+    "...": "..."
+  },
+  "search": {
+    "default": "google",
+    "engines": {
+      "google": "https://google.com/search?q={}",
+      "yahoo": "https://search.yahoo.com/search?p={}",
+      "bing": "https://www.bing.com/search?q={}",
+      "duckduckgo": "https://duckduckgo.com/?q={}",
+      "twitter": "https://twitter.com/search?q={}",
+      "wikipedia": "https://en.wikipedia.org/w/index.php?search={}"
+    }
+  }
+}
+```
 
 ## Licence