It's not all on the Internet!
We all "know" that this poster is true, but many researchers are seduced by the record images and indexes available on the Internet. The availability of records on the Internet has significantly reduced the time it takes to find some useful records of our ancestors (from weeks to hours), and to take an ancestral line back many generations into history (with online family trees). Often, a searcher (not a researcher at this point) does only the Internet search, and then does it again and again, and thinks they are done with their family tree. What is lost due to this easy access is the "analysis" and "critical thinking" time involved in deciding if the record pertains to the persons being searched, and what other records might be found to add to the knowledge base for that person.
The fact is that only about 5% of all genealogical records (according to Gordon Clarke of FamilySearch) are available on the Internet in some format, and the number may be much lower - who knows how many pieces of paper are in national archives, state archives, libraries, genealogical and historical society files, etc. Ancestry.com claims to have about 4 billion records (individuals, not images?), and the LDS Family History Library has about 2.5 million microfilms and about 1 million microfiches with record images (perhaps 2 to 3 billion record images?).
At the San Diego Genealogical Society Seminar on Saturday, Kerry Bartels of the National Archives at Riverside noted that NARA has over 10 billion paper documents in 200,000 databases. He spread his arms wide and said that if that represents all NARA records, then held his hands about four inches apart and said that represents the records that have been microfilmed (3,000 data sets microfilmed - about 1.5%) and then held his fingers about a half-inch apart and said that represents the records imaged and indexed by the FHL, Ancestry, Footnote and others. He estimated that genealogists use only about 5% of all available records.
The takeaway here is that serious genealogists and family historians need to search in ALL of the records, not just online. That includes records on paper, on microfilm or microfiche, in digital indexes and images, and on websites.
The "Iceberg" poster above is exactly right - only a small percentage of records are on the Internet in some format, and the records that are not imaged and indexed are in libraries, courthouses, and archives.