It is powered from a wall socket, as it has no on-board battery, but it is still classed as a portable device since it can be hand-carried when the keyboard is closed.

[3] The Osborne 1 is about the size and weight of a sewing machine and was advertised as the only computer that would fit underneath an airline seat.

The Osborne 1 was described as "a cross between a World War II field radio and a shrunken instrument panel of a DC-3",[5] and Felstenstein admitted that carrying two of them to a trade show "nearly pulled my arms out of their sockets".

[9][10] West Coast Computer Faire attendees stated, InfoWorld said, that the Osborne 1 "represented an advancement of the price/performance ratio for microcomputers".

[7] Adam Osborne agreed but emphasized the price, stating that its performance was "merely adequate": "It is not the fastest microcomputer, it doesn't have huge amounts of disk storage space, and it is not especially expandable.

The Osborne's popularity was surpassed by the similar Kaypro II; which has a larger, 9 inches (23 cm) CRT that can display 80 characters on 24 lines, and double density floppies that can store twice as much data.

The parallel port uses a card-edge connector etched on the main board, exposed through a hole in the case; any IEEE-488 or printer cable has to be modified for the Osborne.

They utilize a custom controller board that Osborne produced, which among other things has a single connector for the power and data lines.

The processor, memory, floppy controller, PIA, ACIA and EPROMs are interconnected with standard TTL devices.

Bank 1 is "normal" mode, where user programs run; this includes a 4 KB area at the top of the address space which is video memory.

[17] The Osborne 1 came with a bundle of application software with a retail value of more than US$1500, including the WordStar word processor, SuperCalc spreadsheet, and the CBASIC and MBASIC programming languages.

[10] The exact contents of the bundled software varied depending on the time of purchase; for example, dBASE II was not included with the first systems sold.

OCC also sold the POWR-PAC inverter that allows running an Osborne from a 12 volt car cigarette lighter.

Osborne 1 systems with the Screen-Pac upgrade have an RCA jack installed on the front panel to allow users to connect an external composite video monitor.

[20] InfoWorld reported that Osborne's booth at the April 1981 West Coast Computer Faire "was packed for the entire show".

Some attendees praised the computer, while others said that the screen was too small; many agreed "that the Osborne 1 represented an advancement of the price/performance ratio for microcomputers", the magazine said.

[7] Jerry Pournelle wrote in BYTE that the small size of the screen surprised him by not being a problem, and stated that after using it at Caltech when Voyager 1 arrived at Saturn, "a dozen science writers were ready to go buy an Osborne 1".

An Osborne and an Epson printer will put you in the computing/word-processing business cheaper than anything I can think of",[21] and later described the computer as "the VW of the microcomputer field: It's cheap, reliable, handles standard programs well".

[22] A separate review in the magazine stated "If you need a solid, well-supported, well-documented business system at a reasonable price, you should give [the Osborne 1] a great deal of consideration".

[citation needed] Freelance journalist David Kline praised the Osborne 1's durability, reporting in 1982 that the "damage inflicted by arrogant customs officers, airport police, vengeful Paris bellhops and opium-fogged Pakistani cabbies were entirely cosmetic".