diff --git a/.gitignore b/.gitignore
deleted file mode 100644
index e69de29..0000000
diff --git a/LICENSE b/LICENSE
index 0ce6454..f635d8d 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2019 Vadim
+Copyright (c) 2019 Vadim Kudriavtcev
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index 6a60076..d4cfa42 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,138 @@
-# Redux-helper
+# Redux Array Helper
 
-Effortless operations with Reducers
+Effortless operations with Reducers.
+
+Motivation - make operations with redux store as simple as possible and keep data immutable.
+
+If you currently doing update like this.
+
+```javascript
+export default function example(state = initialState, action) {
+
+      switch (action.type) {
+
+            case UPDATE: 
+              return { 
+                  ...state, 
+                  list: state.sections.map(item => {
+                        if (item._id !== action.payload._id) {
+                              return item
+                        }
+                        return {
+                              ...item,
+                              ...action.payload
+                        }
+                  })
+            }
+
+            default:
+                  return state;
+
+      }
+
+}
+```
+
+You can do this shorter:
+
+```javascript
+
+export default function example(state = initialState, action) {
+
+      switch (action.type) {
+
+            case UPDATE: 
+              return { 
+                  ...state, 
+                  list: ReduxArrayHelper.update(state.list, action.payload)
+            }
+
+            default:
+                  return state;
+
+      }
+
+}
+```
+
+And many other short operations of CRUD. More examples below.
+
+### Installation
+
+Copy ReduxHelper.js to your project. For example to src/utils/ folder.
+
+### Importing
+
+```javascript
+import { ReduxArrayHelper } from '../utils/ReduxHelper'
+```
+
+### Methods 
+
+| Method | First Arguments | Second Arguments | Third Arguments | Description |
+| ------ | ------ | ------ | ------ | ------ |
+| append | list | payload | - | Insert to the end of the list |
+| prepend | list | payload | - | Insert to the end of the list |
+| insert | list | payload | index | Insert to position of the list |
+| update | list | payload | (optional) comparator | Update item of list by id in the payload |
+| updateByIndex | list | payload | index (int) | Update item of list by payload |
+| delete | list | payload | (optional) comparator | Delete item from the list by id in the payload |
+| deleteById | list | payload (id) | (optional) comparator | Delete item from the list using payload |
+| deleteByIndex | list | index (int) | - | Delete item from the list using payload |
+| find | list | payload | (optional) comparator | Return the item from the list by id in the payload |
+| findById | list | payload (id) | (optional) comparator | Return the item from the list by payload|
+| findIndexById | list | payload (id) | (optional) comparator | Return index of item by payload |
+
+if you are using MongoDB, pass the third argument COMPORATOR as string key '_id'.
+
+```javascript
+ReduxArrayHelper.update(state.list, action.payload, '_id')
+```
+
+### Payload from action.
+
+```javascript
+{
+      id: 1,
+      title: 'Redux the best!',
+      size: 300,
+}
+```
+
+### Reducer
+
+```javascript
+import {
+  CREATE_BOOK,
+  UPDATE_BOOK,
+  DELETE_BOOK,
+} from '../var/Examples'
+
+import { ReduxArrayHelper } from '../utils/ReduxHelper'
+
+const initialState = {
+      list: [
+        { id: 1, title: 'Redux awesome!'}
+      ],
+}
+
+export default function examples(state = initialState, action) {
+
+      switch (action.type) {
+
+            case CREATE_BOOK: 
+                  return { ...state, list: ReduxArrayHelper.append(state.list, action.payload) }
+
+            case UPDATE_BOOK: 
+                  return { ...state, list: ReduxArrayHelper.update(state.list, action.payload) }
+
+            case DELETE_BOOK: 
+                  return { ...state, list: ReduxArrayHelper.delete(state.list, action.payload) }
+
+            default:
+                  return state;
+
+      }
+
+}
+```
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diff --git a/ReduxHelper.js b/ReduxHelper.js
new file mode 100644
index 0000000..d9622a0
--- /dev/null
+++ b/ReduxHelper.js
@@ -0,0 +1,102 @@
+export const ReduxArrayHelper = {
+
+      append: (list, payload) => {
+            if(!list || !Array.isArray(list)) return [payload]
+            let newList = Array.from(list)
+            newList.push(payload)
+            return newList
+      },
+
+      prepend: (list, payload) => {
+            if(!list || !Array.isArray(list)) return [payload]
+            let newList = Array.from(list)
+            newList.unshift(payload)
+            return newList
+      },
+
+      insert: (list, payload, index) => {
+            if(!list || !Array.isArray(list)) return [payload]
+            let newList = Array.from(list)
+            newList.splice(index, 0, payload)
+            return newList
+      },
+
+      update: (list, payload, comparator = 'id') => {
+            if(!list || !Array.isArray(list) || !payload) return list
+            return Array.from(list).map(item => {
+                  if (item[comparator] !== payload[comparator]) {
+                        return item
+                  }
+                  return {
+                        ...item,
+                        ...payload
+                  }
+            })
+      },
+
+      updateByIndex: (list, payload, index) => {
+            if(!list || !Array.isArray(list) || !payload) return list
+            return Array.from(list).map((item, i) => {
+                  if (index !== i) {
+                    return item
+                  }
+                  return {
+                    ...item,
+                    ...payload
+                  }
+            })
+      },
+
+      delete: (list, payload, comparator = 'id') => {
+            if(!list || !Array.isArray(list) || !payload) return list
+            return list.filter((data) => data[comparator] !== payload[comparator])
+      },
+
+      deleteById: (list, payload, comparator = 'id') => {
+            if(!list || !Array.isArray(list) || !payload) return list
+            return list.filter((data) => data[comparator] !== payload)
+      },
+
+      deleteByIndex: (list, payload) => {
+            if(!list || !Array.isArray(list) || (!payload && payload !== 0)) return list
+            return list.splice(payload, 1)
+      },
+
+      find: (list, payload, compare = 'id') => {
+            if(!list || !Array.isArray(list)) return false
+            return list.find((data) => data[compare] === payload.id)
+      },
+
+      findById: (list, payload, compare = 'id') => {
+            if(!list || !Array.isArray(list)) return false
+            return list.find((data) => data[compare] === payload)
+      },
+
+      findIndexById: (list, payload, compare = 'id') => {
+            if(!list || !Array.isArray(list)) return false
+            return list.findIndex((data) => data[compare] === payload)
+      },
+
+      toObjectByKey: (list, key = 'id') => {
+            if(!list || !Array.isArray(list)) return list
+            let cache = {}
+            list.forEach(data => {
+                  cache[data[key]] = data
+            })
+            return cache
+      },
+
+      groupedToObjectByKey: (list, key = 'id') => {
+            if(!list || !Array.isArray(list)) return list
+            let cache = {}
+            list.forEach(data => {
+                  if(!cache[data[key]]) {
+                        cache[data[key]] = [data] 
+                  } else {
+                        cache[data[key]].push(data)
+                  }
+            })
+            return cache
+      }
+
+}
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