The phase (or sometimes called frame) gives information on how to translate individual parts of a gene, the coding exons. Phases 1 & 2 have a different definition in GFF and EnsEMBL format!
One of the most common question after your Next-Generation Sequencing (NGS) run is: “What is the coverage I achieved?” Unfortunately there a different definitions available for the term “coverage”.
To display data as bar graphs along the genome e.g. in the UCSC genome browser, you can create BigWig files. DeepTools is a powerful library that can also help with this.