XPath
The thumb rule of XPath:
/child::lectures/child::lecture[@number='0']
- /child::lectures is the step part. (Generally, child:: can be omitted)
- child is the axis part. (Also can be decedent, ancestor, attribute)
- lecture is the node test part.
- [@number='0'] is the predicate part. (@number is abbreviation of attribute::number )
The whole cause is called location path.