This is syntactically correct:

```
for f in *bw;do echo $f;done

```

But How would I add an extension to loop through one or the other?

* The following doesn't work:

```
for f in *bw|*txt;do echo $f;done

```
* And this doesn't work either:

```
for f in *bw or *txt;do echo $f;done

```