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### 4.5 Drawing Things in Parallel

Sometimes it is desired to express that two separate process happen side-by-side. The easiest way to do so is to write ‘`parallel`’ before any arrow, box or other element. As a result the elements after it will be drawn in parallel with it.

It is also possible to have bigger blocks of action in parallel using Parallel blocks. Consider the following example.

In the above example a central sever is querying two `AR` entities, which, in turn query `MN` entities further. The query on both sides happen simultaneously. To display parallel actions side by side, simply enclose the two set of arrows between braces ‘`{}`’ and write them one after the other. Use only a single semicolon after the last block. You can have as many flows in parallel as you want. It is possible to place anything in a parallel block, arrows, boxes, or other parallel blocks, as well. You can even define new entities or turn them on or off inside parallel boxes.

The top of each block will be drawn at the same vertical position. The next element below the series of parallel blocks (the "Now I have it" box in our example) will be drawn after the longest of the parallel blocks.