BASH

Ranges

touch file-{1..8}.txt

This touches 8 seperate files of name file-1.txt through file-8.txt.

For each in Loop

for file in *; do echo $file; done
# OR
for file in *;
do
    echo $file;
done

By using the for SOME_VAR in SOME_MULTILINED_OR_GLOB; do SOME_CMDS; done pattern you can loop through every item in a multilined (how bash knows something is a collection), collection of entities and perform a set of commands on each of them individually. Kind of like the for some_var in some_collection in [[python]]. This could also be modified to perform this action on a range.

for num in {1..8}; do echo $num; done;

This for loop uses the for-in loop structure and the {x..y} range structure to create a range of inputs to loop through echo'ing the numbers 1 through 8 in their own line.

The glob pattern shown above can also be changed when specifying the for loop as it's often used for files to only iterate through some pattern, say only .jpg files.

for file in *.jpg; do echo $file; done