The terms are presented in next key: British term / American term.
Let us consider the diagram of simple openwork pattern:



Each stitch has the sequence one after another.


The work begins with the chain foundation of 16 chains.1 row: 1 turning chain, 1 double crochet / single crochet in second chain from hook, * 3 chains, 2 chains miss, 1 double crochet / single crochet in next chain, repeat from * to end of row.


2 row: 3 turning chains, 1 chain, 1 treble / double crochet in the space of 3 chains bellow, * 4 chains, 1 double crochet / single crochet in the space of 3 chains bellow, 4 chains, 1 treble / double crochet in the space of 3 chain bellow, repeat from * 1 time, 1 chain and 1 treble / double crochet in double crochet / single crochet bellow. 

Every stitch has an own symbol:


3 row: 1 turning chain, 1 double crochet / singlr crochet in treble / double crochet, * 3 chains, 1 double crochet / single crochet in the space of 4 chains bellow, repeat from * 4 times.

4 row: 3 turning chains, 3 chains and 1 double crochet / single crochet in the space of 3 chains bellow, * 4 chains, 1 treble / double crochet in the space of 3 chains bellow, 4 chains, 1 double crochet / single crochet in the space of 3 chains bellow, repeat from * 1 time, 2 chains and 1 treble / double crochet in double crochet / single crochet bellow.

5 row: 1 turning chain, 1 double crochet / single crochet in treble / double crochet,* 3 chains, 1 double crochet / single crochet in the space of 4 chains bellow, repeat from * 3 times, 3 chains and 1 double crochet / single crochet in space of 6 chains bellow.

Repeat rows 2-5.

Let us consider the diagram of round motif:






The work begins with the chain foundation of 5 chains and joining it to a ring with slip stitch.

1 row: 9 tuning chains, * 1 double treble / treble in ring, 4 chain, repeat from* 6 times, slip stitch to fifth chain of 9 chains.

2 row: 1tuning chain, 1 double crochet / single crochet in same stitch, * [1 double crochet / single crochet, 1 half treble / half double crochet, 3 treble / double crochet, 1 half treble / half double crochet, 1 double crochet / single crochet ] in space of 4 chains bellow, 1 double crochet / single crochet in double treble / single crochet bellow, repeat from * 7 times, slip stitch to turning chain.

3 row: 13 tuning chains, * 1 double treble / single crochet in the second of three double crochet / single crochet bellow, 8 chains, repeat from * 6 times, slip stitch to fifth chain of 13 tuning chains.

4 row: 1 tuning chain, * [ 3 double crochet / single crochet, picot of 5 chains, 4 double crochet / single crochet, picot of 5 chains, 4 double crochet / single crochet, picot of 5 chains, 3 double crochet / single crochet ] in space of 8 chains bellow, repeat from * 7 times, slip stitch to tuning chain.
Source: MyPicot.com