Globular clusters typically have hundreds of thousands of stars and are much older than open clusters. The over one hundred
globulars that belong to the Milky Way galaxy are thought to have formed at the same time as the galaxy itself; well over ten billion
years ago.
Globular clusters have very different color magnitude diagrams. The cluster will tend to have low mass stars, so you will not find any O or B type
stars. There are a fair number of red giants in the clusters, but virtually no white dwarfs.