Could you explain the difference between `STAR`, `KALLISTO`, `SALMON` etc. to experimental Biologist/non-bioinformatician.

If possible, the pros and cons of each pipeline. 

**Edit below**

 ***I ask this because three of my colleagues use this 3 difference tools for RNASeq. Basically to answer the same type of biological questions.***
STAR is a general purpose aligner.  It can align reads to a genome or transcriptome, or whatever you provide.  It can perform spliced alignment, and returns base-level alignments for the reads.  These alignments can then be used for different purposes like being fed to transcript assembly tools, variant calling pipelines, or transcript quantification tools (e.g. you can use STAR to provide alignments to salmon).  

The other tools are both transcript quantification tools.  They map reads to the transcriptome and apply statistical inference to determine transcript abundances.  They serve a different general purpose compared to STAR.  It's worth noting that STAR has the ability to count reads mapping to different genes, and so can be used to estimate gene level abundances, but has no statistical model and so doesnt infer transcript abundance or deal with gene multimapping reads in a principled manner.