Using the Menu...

Select Evaluation Evaluate Notebook to evaluate all the cells in a notebook:

By Selecting All Cells...

Select all the cells in a notebook with Edit Select All () and evaluate them with :

Initialization Cells Only...

To evaluate just a notebooks initialization cells, choose Evaluation Evaluate Initialization Cells:

With the Menu...

Select Evaluation Evaluate All Cells to evaluate all the cells in a notebook:

By Selecting All Cells...

With the insertion point between cells, select all the cells in a notebook with and evaluate them with :

Select ... Evaluate All Cells to evaluate all the cells in a notebook:

Notes

The first time you evaluate all the cells in a notebook that contains initialization cells, you will get a dialog asking if you want to evaluate initialization cells first. If you answer "Yes", the initialization cells will be evaluated twice (which is usually ok). If you answer "No", all cells will be evaluated in the order they occur in the notebook. If the initialization cells do not come first in the notebook, subsequent evaluations may fail.