Blender is a powerful 3D modeling software that allows users to create stunning 3D models for games, animations, and more. One of the most common file formats for sharing 3D models is OBJ, and Blender makes it easy to export your creations in this format. Here's a step-by-step guide on how to export OBJ in Blender:

1. Open your 3D model in Blender: Before you can export your model as an OBJ file, you'll need to have it open in Blender. If you haven't created your 3D model yet, you can start by using Blender's modeling tools to design your object.

2. Select the object you want to export: In Blender, you can have multiple objects in your scene. Make sure to select the specific object or objects you want to export as an OBJ file.

3. Go to File > Export > Wavefront (.obj): Once you've selected the object you want to export, go to the 'File' menu at the top of the Blender window. From there, navigate to 'Export' and then select 'Wavefront (.obj)' from the list of export options.

4. Adjust export settings: After selecting the OBJ export option, a new window will pop up with several settings for the OBJ file. You can adjust the scale, forward, up, and other options to make sure the exported file matches your preferences.

5. Choose a location and save the file: Once you've adjusted the export settings, you can choose a location on your computer to save the OBJ file. Give the file a name and click 'Export OBJ' to save it to your chosen location.

6. Share your OBJ file: Now that you've successfully exported your 3D model as an OBJ file, you can easily share it with others for collaboration, 3D printing, or use it in other software.

By following these simple steps, you can quickly export your 3D models as OBJ files in Blender, making it easy to share and collaborate with others. Whether you're a beginner or an experienced 3D artist, Blender's export tools make it simple to share your creations with the world.