How does it store its data? (e.g., in-memory database vs on drive)
What indexes does it support?
Is it relational or non-relational?
Does it support ACID properties?
how does it handle concurrency control?
how does it handle recovery and logging?
Explain what workloads do you think it should be used for (and why)? (OLAP? OLTP? ...etc)
What are its pros? its cons?
Toad for SQL Server is a client IDE that facilitates working with SQL Server, whether you're a DBA, developer, or even a data analyst, all can use the product to extract and work with the SQL Server database.
All of your questions are asked in the context of the database, not of Toad. e.g. Toad is neither relational nor non-relational, since it is not a database. Toad works with your SQL Server database, so that you can manage data, indexes, tables, procedural code, debug, tune SQL queries, compare and sync schemas and data, etc. etc.
For more info, see...