Plain English

'Plain English' is language that the intended audience can understand and act upon from a single reading.
                                                                               ---Plain English Campaign                         

Benefits of Plain English

Precisio: expressing exactly what you intend
Clarity: producing clear and ambiguous writing
Readability: easy to read and absorb at one sitting
Efficiency: less to write and less to read
Accountability:increasing the sense of involvement and responsibility
Credibility:strengthening the personal quality of trust

Example 1:
Before
High-quality learning environments are a necessary precondition for facilitation and enhancement of the ongoing learning process.
After
Children need good schools if they are to learn properly.

Example 2:
Before
If there are any points on which you require explanation or further particulars we shall be glad to furnish such additional details as may be required by telephone.
After
If you have any questions, please phone.

Example 3:
Before
It is important that you shall read the notes, advice and information detailed opposite then complete the form overleaf (all sections) prior to its immediate return to the Council by way of the envelope provided.
After
Please read the notes opposite before you fill in the form. Then send it back to us as soon as possible in the envelope provided.

Example 4:
Before
Your enquiry about the use of the entrance area at the library for the purpose of displaying posters and leaflets about Welfare and Supplementary Benefit rights, gives rise to the question of the provenance and authoritativeness of the material to be displayed. Posters and leaflets issued by the Central Office of Information, the Department of Health and Social Security and other authoritative bodies are usually displayed in libraries, but items of a disputatious or polemic kind, whilst not necessarily excluded, are considered individually.
After
Thank you for your letter asking for permission to put up posters in the library. Before we can give you an answer we will need to see a copy of the posters to make sure they won't offend anyone.

Source: http://www.plainenglish.co.uk/