This paper offers an insight on the future of tribology. Simulation approach can avoid expensive tests, by using available experimental data from existing databases. Predictive solutions can be found from machine learning algorithms and artificial neural networks models (ANN).

The subject of the paper is interesting, but this review misses important points. I have some questions and suggestions for the authors.

1. Why only molecular dynamics and finite elements method (FEM) is important?! A general logical diagram of life cycle assessment (LSA) of components would help the reader to understand the path to follow. The diagram of Figure 2 is more than insufficient. Where is the place of molecular dynamics model in Figure 2, and why only molecular dynamics is considered?

2. Considering the above mentioned aspects, the entire paper must be rearranged. There is macro, micro, and nano tribology. Please include some considerations on each of them.

3. If this is a review work, it should not provide details on some models. If possible, try to compress this very long paper, by concentrating only on important aspects of tribology. For example, the sections for molecular dynamics and FEM simulation could miss the equations. In my opinion, graphical representations of practical examples and diagrams would be more attractive. As it is, your work offers nor a solution to life cycle assessment of components from tribological viewpoint, neither complete models.

4. The second phrase of Introduction (lines 31-32) should be reformulated or deleted.

This paper presents a review on the existing problems in tribology field, emphasizing the importance of both computer aided simulation and physical experimentation. Also, the paper underlines that the future simulations and life cycle assessment (LCA) of tribological pairs requires a large database of experimental work and machine learning (ML) algorithms and predictive artificial neural networks (ANN).

The review is rich in information but, in my opinion, it is still difficult to read and to follow a general aim, or a general idea. Unfortunately, there still are some phrases requesting amendments, like those from lines 77-79, 99-101, or 124-127. I advise the authors to carefully analyze the paper, trying to group the similar ideas in the same section, e.g., the description of hip simulator in industrial applications section is not suited. This should be included in the section containing the description of tribometers.

I realize the huge effort made by the authors to bring the paper to publication standards, so I ask for a major revision from the reasons presented above.

I suggest to the authors to compress Tables 1 and 2, eventually decreasing the text size. Also, Notations and symbols and Table of contents should be placed at the end of the paper. Finally, I congratulate the authors for their work.