These are all project pouches, a means of storing or carrying or working from fibre projects such as knitting or crocheting or needle felting etc.
They all are created from squares.
The upper left one is made from plastic that was meant to line drawers; the two felted ones to the right began as knitted yin yang squares; the one below them is a slight variation using clear heavy gauge plastic; the bottom left is again a yin yang square knit from 'beginners' handspun' but not felted.
Here two of them are in their 'seated' position to illustrate how they 'sit' and hold the project when you are working on it or simply being displayed in the house. The bottom is triangular and in these three buttons have been sewn on the corners to give 'feet' and character.
This shows the bottom of the translucent one which does not have buttons. Also note where it it stitched – along two bottom edges and part-way up the front.
This is the pouch standing – slopes forward slightly and reminded me of a kangaroo's carrying case, thus the name "pouch".
The method is to take any square and fold three corners in on itself as shown. The two edges that meet are then sewn; the edges illustrated by the arrows are then sewn (or simply attached as in the transluscent one using rope threaded through paper punch holes) which forms the pouch; sew as much as suits the desired result. 
I pin it first to get the feeling of the finished size and look of the pouch and adjust accordingly using a glass, in this case, to suggest a project in the pouch. The blue pins are the bottom two edges, the red pin the front seam.
The fourth corner of the square is turned back on itself and forms a slot through which to thread a handle or shoulder strap or waist belt; these two are either i-cord or Greek braid, can't remember which, both felted.
It makes a handy receptacle if you want to walk and 'work' or have the project available when lining up in the bank or at the post office etc.
I love the conversations that inevitably happen at such times.
The small pouch is more for keys but it you knit miniatures it can easily accommodate the 1/12 scale and makes an attractive necklet.
The clear plastic pouch is an adaptation in that I extended the original folds so got more of a pocket than a pouch and added fringe.
Experiment!