diff --git a/builds/readme.md b/builds/readme.md
new file mode 100644
index 0000000..b16c31f
--- /dev/null
+++ b/builds/readme.md
@@ -0,0 +1,12 @@
+My API Call would be to  
+
+REACT_APP_API_BASE_URL  
+
+so we can use 
+
+.env.production.local for our production build
+and 
+.env.development.local for our development
+
+in these files we could savly store our different FQDNs
+
diff --git a/cars/index.js b/cars/index.js
new file mode 100644
index 0000000..41ff887
--- /dev/null
+++ b/cars/index.js
@@ -0,0 +1,69 @@
+const express = require('express')
+const app = express()
+const mongoose = require('mongoose')
+const Car = require('./models/cars')
+
+const dbURI = `mongodb+srv://cars:cars!"§$@cluster0.58qos.mongodb.net/myFirstDatabase?retryWrites=true&w=majority`
+
+mongoose.connect(dbURI, { useNewUrlParser: true, useUnifiedTopology: true })
+    .then(() => app.listen(3000, () => console.log("running")))
+    .catch(err => console.log(err))
+
+
+app.get("/add", (req, res) => {
+    const car = new Car({
+        car_id: 2,
+        available: {
+            from: 50,
+            to: 200
+        },
+        reserved: [
+            {
+                from: 55,
+                to: 70
+            },
+            {
+                from: 120,
+                to: 130
+            }
+        ]
+    })
+    car.save()
+        .then(result => res.json(result))
+        .catch(err => res.json(err))
+})
+
+// Possible Query
+// {
+//     $and: [
+//         {
+//             reserved: {
+//                 $not: {
+//                     $elemMatch: {
+//                         from: { $lte: 2 },
+//                         to: { $gte: 10 }
+//                     }
+//                 }
+//             }
+
+//         }, {
+//             available: {
+//                 from: { $lte: 2 },
+//                 to: { $gte: 10 }
+//             }
+//         }
+//     ]
+// }
+
+
+// {
+//     reserved: {
+//         $not: {
+//             $elemMatch: {
+//                 from: { $lte: 2 },
+//                 to: { $gte: 10 }
+//             }
+//         }
+//     }
+
+// }
\ No newline at end of file
diff --git a/cars/models/cars.js b/cars/models/cars.js
new file mode 100644
index 0000000..78e2345
--- /dev/null
+++ b/cars/models/cars.js
@@ -0,0 +1,26 @@
+const mongoose = require('mongoose')
+const Schema = mongoose.Schema
+
+const carSchema = new Schema({
+    car_id: {
+        type: Number,
+        required: true
+    },
+    available: {
+        from: {
+            type: Number,
+            required: true
+        },
+        to: {
+            type: Number,
+            required: true
+        }
+    },
+    reserved: {
+        type: Array,
+        required: false
+    }
+}, { timestamps: true })
+
+const Car = mongoose.model('car', carSchema)
+module.exports = Car
\ No newline at end of file
diff --git a/cars/readme.md b/cars/readme.md
new file mode 100644
index 0000000..eb5550f
--- /dev/null
+++ b/cars/readme.md
@@ -0,0 +1,25 @@
+My car model should have 
+
+available: {
+            from: time_start,
+            to: time_end
+        },
+reserved: [
+    {
+        from: time_start,
+        to: time_end
+    },
+    ...
+]
+
+My query should look if there is any overlap between the reserved time
+{
+    reserved: {
+        $not: {
+            $elemMatch: {
+                from: { $lte: start_time },
+                to: { $gte: end_time }
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/deduplicate/main.js b/deduplicate/main.js
new file mode 100644
index 0000000..b4f79ea
--- /dev/null
+++ b/deduplicate/main.js
@@ -0,0 +1,21 @@
+const wordList = ['not', 'a', 'pheasant', 'plucker', 'but', 'a', 'pheasant', "plucker's", 'son']
+// [ 'not', 'a', 'pheasant', 'plucker', 'but', 'plucker\'s', 'son' ]
+
+// let temp = JSON.stringify(wordList).replace("'", "\\'")
+// let temp2 = JSON.parse(temp)
+// console.log(temp2)
+
+// const filterArray = (array) => [...new Set(array)].map(ele => JSON.stringify(ele))
+const filterArray = (array) => [...new Set(array)]
+// const filterArray = (array) => [...new Set(array)].map(ele => ele.replace(/'/g, '"').replace(/"/g, String.fromCharCode(92, 39)))
+// with help of spread Operator and new Set we will have an array with unique values
+
+const filterArray2 = (array) => array.filter((element, index, array) => (array.indexOf(element) === index))
+// const filterArray2 = (array) => array.filter((element, index, array) => (array.indexOf(element) === index)).map(ele => ele.replace("'", String.fromCharCode(92)))
+// we look, where the first apperance of this element is. If it is the index it is the first time it apperce.
+// If the number is bigger we dont return the element because it's already there
+
+console.log(filterArray(wordList))
+
+// Prefered Method: (if ES6 is available) new Set
+
diff --git a/deduplicate/trys.js b/deduplicate/trys.js
new file mode 100644
index 0000000..3d7183f
--- /dev/null
+++ b/deduplicate/trys.js
@@ -0,0 +1,24 @@
+// const filterArray3 = (array) => array.filter((element, index, array) => (array.indexOf(element) === index)).map(ele => {
+//     if (ele.indexOf("'") !== -1) {
+//         let first = ele.slice(0, ele.indexOf("'"))
+//         console.log(first)
+//         let middle = "\\'"
+//         console.log(middle)
+//         let rest = ele.slice(ele.indexOf("'") + 1)
+//         console.log(rest)
+//         console.log(first + middle + rest)
+//         let alles = first + middle + rest
+//         console.log(alles)
+//         return alles
+//     } else {
+//         return ele
+//     }
+// })
+
+
+
+// The \ in 'plucker\'s' is a problem. 
+// tried:
+// replace
+// \x27
+// String.fromCharCode(92)
\ No newline at end of file