There are a huge number of embroidery stitches - all based on simple movements of the needle. Before the widespread use of books and patterns "samplers" of stitches were often created. A sampler began simply as a piece of cloth with examples of stitches and patterns. These acted as reminders and pattern references - and were often handed down through the generations. Some were decorative, others practical (as in darning samplers).
Some used very simple stitches to decorate the fabric, other more complex, some altered the fabric with cut work. There were "spot samplers" of motifs,"band samplers" showing borders and repetitive patterns and often a mix of the two.
Domestic staff would take samplers along to prove their needlework skills to new employers.
Later they were often created by small children of the upper classes (as young as 4yrs old) to practise and improve their skills.
All of the samplers below are English and shown in chronological order so that you can see the progression from reference works to art works.