Sources of data

The course notes explain that: Stratified: If the population was 60% women, 40% men, then 60% of the sample should be women and 40% men. Quota: Population is 60% women and 40% men. We want to question a sample of 200. Decide on a quota of 120 women (60%) and 80 men(40%), and stop people as they appear until we have the required number. The only difference I see is the way in which candidates are chosen (one by one until the quota is satisfied), however, in stratified sampling, it makes no reference to how the 60% and respective 40% are selected. I'm a little confused,any help would be greatly appreciated.