SKP files are created using SketchUp, a popular 3D modeling program. If you've received an SKP file but don't have SketchUp installed on your computer, don't worry! You can still view and open SKP files online using a variety of tools and viewers. Here's how:

1. Use SketchUp Free: SketchUp offers a free web-based version of their software called SketchUp Free. Simply visit their website and sign in to your Trimble account, then upload the SKP file to view and edit it online.

2. Convert to other formats: If you're unable to open the SKP file directly, you can convert it to other file formats like STL or OBJ using online conversion tools. Once converted, you can use a variety of 3D viewers to open and interact with the file.

3. Online SKP viewers: There are several online SKP viewers available that allow you to upload and view SKP files without having SketchUp installed. These viewers often provide basic editing capabilities as well, making it easy to collaborate with others on SKP files.

4. Use 3D modeling software: Some online 3D modeling software also supports the opening and viewing of SKP files. Look for web-based 3D modeling tools that have the capability to import SKP files for viewing and editing.

By using these methods, you can easily open and view SKP files online without the need for SketchUp or other specific software. Whether you're collaborating on a project or simply need to view a 3D model, these online tools and viewers make it easy to access SKP files from anywhere with an internet connection.