First, welcome to Manresa On The Mississippi. The goal for your retreat is to make yourself completely open and available to the Lord. To accomplish this, St. Ignatius calls for silence, both external and internal. This means that the retreatant refrains from all conversation with fellow retreatants. Although silence is almost always mandatory, there are ways to ask someone to pass the salt to you during meals. The only exceptions to silence are during Mass, Benediction, the Rosary, the Way of the Cross, and the prayers before and after meals. Yes, you can chuckle at the presenter's jokes.
On the more serious side, as said before, the goal for your retreat is “for interior knowledge of the Lord… that I may more love and follow Him.” Manresa is blessed with beautiful grounds which are conducive to do just that: just God and you. Silence begins at the conference on the first evening and ends after the Blessing Before Meals for Sunday's lunch.