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+A lot of genomics analysis is done using command-line tools for three reasons: 1) you will often be working with a large number of files,
+and working through the command-line rather than through a graphical user interface (GUI) allows you to automate repetitive tasks, 2) you
+will often need more compute power than is available on your personal computer, and connecting to and interacting with remote computers
+requires a command-line interface, and 3) you will often need to customize your analyses and command-line tools often enable more 
+customization than the corresponding GUI tools (if in fact a GUI tool even exists). 
+
+In a previous lesson, you learned how to use the bash shell to interact with your computer through a command line interface. In this 
+lesson, you will be applying this new knowledge to carry out a common genomics workflow - identifying variants among sequencing samples 
+taken from multiple individuals within a population. We will be starting with a set of sequenced reads (`.fastq` files), performing
+some quality control steps, aligning those reads to a reference genome, and ending by identifying and visualizing variations among these
+samples. 
+
+As you progress through this lesson, keep in mind that, even if you aren't going to be doing this same workflow in your research, 
+you will be learning some very important lessons about using command-line bioinformatics tools. What you learn here will enable you to 
+use a variety of bioinformatic tools with confidence and greatly enhance your research efficiency and productivity.
 
 > ## Prerequisites
 >