CREATE TABLE table_203_580 (id DECIMAL, "title" TEXT, "release" DECIMAL, "genre" TEXT, "computer" TEXT, "console" TEXT, "handheld" TEXT, "smartphone" TEXT)

which kind of computer can most of the games be played on ?
SELECT "computer" FROM table_203_580 GROUP BY "computer" ORDER BY COUNT("title") DESC LIMIT 1
SELECT "computer" FROM "table_203_580" GROUP BY "computer" ORDER BY COUNT("title") DESC NULLS LAST LIMIT 1