You can create sequence diagrams like this:
```sequence
Alice->Bob: Hello Bob, how are you?
Bob-->Alice: I am good thanks!
```
More info
Or flow charts like this:
```flow
st=>start: Start
e=>end
op=>operation: My Operation
cond=>condition: Yes or No?
st->op->cond
cond(yes)->e
cond(no)->op
```
More info