diff --git a/src/mapmarkers/mapmarker.dto.ts b/src/mapmarkers/mapmarker.dto.ts
index eab9dc6c55d4a1aeada99bf82b37f1ce2cb10ca1..f9821f4cbc73b62582263ac63e29c07a75a46b44 100644
--- a/src/mapmarkers/mapmarker.dto.ts
+++ b/src/mapmarkers/mapmarker.dto.ts
@@ -1,5 +1,9 @@
-import { IsString, IsDateString } from 'class-validator';
-import { Timestamp } from 'typeorm';
+import { IsString, IsJSON } from 'class-validator';
+/*
+DTO: MapMarker
+- represents servers data handling.
+*/
+
 
 export class MapMarkerDTO {
     @IsString()
@@ -10,4 +14,6 @@ export class MapMarkerDTO {
     longitude: string;
     @IsString()
     timestamp: string;    
+    @IsJSON()
+    features: JSON;
 }
\ No newline at end of file
diff --git a/src/mapmarkers/mapmarker.entity.ts b/src/mapmarkers/mapmarker.entity.ts
index 39ff2b2663473acba2ca17d9b13ed8be3a845c41..41a955d3998702c15ca0429b9e92bad936ced49c 100644
--- a/src/mapmarkers/mapmarker.entity.ts
+++ b/src/mapmarkers/mapmarker.entity.ts
@@ -2,12 +2,18 @@ import { Entity, Column, PrimaryGeneratedColumn, Timestamp, ManyToOne } from 'ty
 
 import { PersonEntity } from 'src/user/user.entity'
 
+/*
+Entity: MapMarker 
+- represents data that database contains on mapmarker
+*/
+
 @Entity('MapMarker')
 export class MapMarkerEntity {
     @PrimaryGeneratedColumn('uuid') id: string;
     @Column({type: 'text'}) latitude: string;
     @Column({type: 'text'}) longitude: string;
     @Column({type: 'timestamp'}) timestamp: Timestamp;
+    @Column({type: 'json', nullable: true}) features: JSON;
     @ManyToOne(type => PersonEntity, player => player.markers)
     player: PersonEntity;
 }
\ No newline at end of file
diff --git a/src/mapmarkers/mapmarker.service.ts b/src/mapmarkers/mapmarker.service.ts
index 5235e4b4abbe0e5573be32145cdb131dc995ffda..c47ddf0f9ce2773addb34c05e8a77d296b8cf713 100644
--- a/src/mapmarkers/mapmarker.service.ts
+++ b/src/mapmarkers/mapmarker.service.ts
@@ -10,6 +10,7 @@ import { userInfo } from 'os';
 @Injectable()
 export class MapMarkerService {
     constructor(
+        //create references to tables as repositories
         @InjectRepository(MapMarkerEntity) private mapmarkerRepository: Repository<MapMarkerEntity>,
         @InjectRepository(PersonEntity) private personRepository: Repository<PersonEntity>
     ) { }
@@ -17,10 +18,15 @@ export class MapMarkerService {
     // insert markers
     async insertLocation(personId: string, data: MapMarkerDTO) {
         try {
-            data.timestamp = new Date(Date.now()).toLocaleString(); //get functions runtime as timestamp
+            //get functions runtime as timestamp
+            data.timestamp = new Date(Date.now()).toLocaleString(); 
+            //check from database for the user who uploads the data
             const user = await this.personRepository.findOne({ where: { id: personId } })
+            //create&copy entity properties
             const location = await this.mapmarkerRepository.create({ ...data, player: user });
+            // insert created entity NOTE: insert method doesn't check for duplicates.
             await this.mapmarkerRepository.insert(location);
+            // return data and player id&name
             return { ...data, player: location.player.nameObject() };
         } catch (error) {
             return error;
@@ -30,7 +36,9 @@ export class MapMarkerService {
     // get all markers
     async getAllMarkers() {
         try {
+            // find all markers with specified player
             const markers = await this.mapmarkerRepository.find({ relations: ['player'] });
+            // return markers from database with said playerdata
             return markers.map(marker => { return { ...marker, player: marker.player.nameObject() } });
         } catch (error) {
             return error.message;
diff --git a/src/mapmarkers/mapmarkers.controller.ts b/src/mapmarkers/mapmarkers.controller.ts
index f6c2e0ba8b3242be35f0f99bbdeb020a08e68f55..6aa89c9f3949e1fa39e64779bbc073df46ac0c6b 100644
--- a/src/mapmarkers/mapmarkers.controller.ts
+++ b/src/mapmarkers/mapmarkers.controller.ts
@@ -20,7 +20,7 @@ export class MapMarkersController {
         }
     }
 
-    // return all markers
+    // return all markers through service
     @Get('getall')
     async getAll(){
         return this.mapmarkerservice.getAllMarkers();