What are different kinds of dashboard component

1. Chart: Use a chart when you want to show data graphically.

2. Gauge: Use a gauge when you have a single value that you want to show within a range of custom values.

3. Metric: Use a metric when you have one key value to display.

• Enter metric labels directly on components by clicking the empty text field next to the grand total.
• Metric components placed directly above and below each other in a dashboard column are displayed together as a single component.

4. Table: Use a table to show a set of report data in column form.

5. Visualforce Page: Use a Visualforce page when you want to create a custom component or show information not available in another component type

6. Custom S-Control: Custom S-Controls can contain any type of content that you can display or run in a browser, for example, a Java applet, an ActiveX control, an Excel file, or a custom HTML Web form

What is Permission sets in Salesforce.

A permission set is a collection of settings and permissions that give users access to various tools and functions. The settings and permissions in permission sets are also found in profiles, but permission sets extend users’ functional access without changing their profiles. 

For example, to give users access to a custom object, create a permission set, enable the required permissions for the object, and assign the permission set to the users. You never have to change profiles, or create a profile for a single use case. While users can have only one profile, they can have multiple permission sets.
Permission sets include settings for:

• Assigned apps
• Object settings, which include:
• Tab settings
• Object permissions
• Field permissions
• App permissions
• Apex class access
• Visualforce page access
• System permissions
• Service providers (only if you’ve enabled Salesforce as an identity provider)

In salesforce which fields are indexed automatically?

The following fields are indexed by default:

• primary keys (Id, Name and Owner fields),
• foreign keys (lookup or master-detail relationship fields),
• audit dates (such as LastModifiedDate),
• Custom fields marked as External ID or Unique