"Why would I want to see the SMILES string?", you may ask. Suppose you have already entered a structure into Neighbor_Search or Neighbor_Search has found some interesting near-neighbor compounds. Select (using Edit/Copy from the browser menu) the SMILES string and paste it into the ID field of Neighbor_Search. Then press the Grins editor button. The structure will be depicted on the next page. You may then go on to the Grins editor which will start with the structure you have entered. So for example, you may retreive SC-58125, toggle on the SMILES display, cut&paste the SMILES string into the ID field and press the Grins editor to create a substituted SC-58125.
SMILES is a line notation useful representing a molecular structure. You can learn more (than you probably want to know) about SMILES. It is one of the ways to enter your compounds into Neighbor_Search. If you do not have an SC or CP number (or ACD, CAP or other database number), it is the ONLY way to enter molecular structures into Neighbor_Search. SMILES is not hard to learn, though it can be complex for complex structures, such as fused ring systems.
If you need to input a structure to Neighbor_Search and you don't have a datbase number, there are two graphical ways to draw your structure.