Does Google know about you? Yes! Up to certain extent? No, everything! Shocking right? Yes, if you use most of the Google products including Gmail, Gdrive, Maps and more. You can see all the things you did in a specific page called "My Activity".
What is My Activity? This is a hub where you can see all the information Google has been collecting about you over time. In here you will see activity including Search, Image Search, Maps, Play, Shopping, YouTube, and more.
Also, you can see a list of each individual item on the timeline by clicking the menu button in the upper left corner and heading onto Item view. Google uses your data to improve its services for the general population and to give you a more personalized experience.
Is there any option to delete it? If yes, how?
Yes, there is! You can delete everything from the My Activity page.
If you want to delete individual items from the My Activity page, find it and click the three dots next to it and then click Delete.
To delete it from a specific day say past week, the past month, click the menu button in the upper left corner of the My Activity page and click Delete activity by. You can choose to delete an activity from today, yesterday, the last 7 days, the last 30 days, or from all time.
To delete activity by the app, such as YouTube, go to the My Activity page and click Filter by date & product under the Search box. Now, choose the product you want and delete an activity from and click the Search button.
Can I Stop it?
Yes, you can! Click the menu in the upper left corner and click Activity controls. Now it will show you the list -- Web & App Activity, Location History, Device Information, Voice & Audio Activity, YouTube Search History, and YouTube Watch History. If you want them to stop tracking you, just turn off the toggle next to the option.