Designing an Effective Search Facility

Given that there are situations (large, content or product rich site, for example) when users are likely to require a search facility, it is worth considering best practise in terms of displaying results in a way that assists users find what they are looking for.

Whilst some designers would insist that to even contemplate adding a search engine to a site is to admit some sort of failure of interaction design, most would agree that in certain circumstances some form of search facility can be appropriate. Either way, it is an issue that sooner or later is likely to be addressed by many site developers.

It is important to recognise that when we speak of a 'search facility' we are often applying one catch-all name to what is in fact many distinct functions. There is a significant difference, for example, between searching for specific items with specific names (such as books in a bookshop) and looking for any documents that contain certain words or phrases. The former is a targeted, 'hard' search, the latter a much more complex 'soft' process that is likely to place greater demands on the user if they are to be successful. Although in terms of interface design and technology these searches may be similar, for the user they are very different processes.

Searches are often the quickest and easiest way to locate information, but it must be understood that the search process places an increased burden on the user. In order to work efficiently, search terms must be carefully chosen and spelt correctly. Most importantly, they are unprompted. For this reason many users prefer to find information through navigation schemes if possible - and this is why some feel that using search engines when they are not really required is likely to reduce efficiency levels.

However, given that there are situations (large, content or product rich site, for example) when users are likely to require a search facility, it is worth considering best practise in terms of displaying results in a way that assists users find what they are looking for. Search engine designers should consider the following:

• If relevant, prompt users before they input search terms. By giving an example of the type of terms that might be appropriate, the interface can reassure user that they are using the engine in the correct way and reduce time spent 'second guessing' the engine.
• Ensure search results provide enough information to assist the user. A meaningful title and concise, informative summary will make search results easier to comprehend and help users choose the right link when confronted with lengthy listings.
• Enable advanced users to refine searches, use multiple search 'filters', or use 'boolean' queries in order to narrow down search results. However, make sure these features are not so prominent as to confuse novice users who may lack confidence with these techniques.
• Make sure that information returned from searches is only included when relevant or appropriate. Although 'last modified' dates and URLs may be helpful for some users, others may find them distracting. Depending on the audience, consider the merits of each element and remove any that are unnecessary.

Of course, this advice is dependent on the search engine itself working effectively. If you are not confident that the engine you are using is returning relevant results, for whatever reason, it is best to remove a search engine altogether - to do otherwise is just wasting the user's time.