The TRS-80 is, to put it simply, a computer. In fact, it was one of the first computers on the market. Sold by the Tandy Corporation in the 1970's and 80's, the TRS-80 combined the motherboard and the keyboard into one unit with a separate monitor. Think Apple's iMac — just less sleek and modern. These early computers used tape and floppy disks for data storage rather than a hard drive. The TRS-80 shipped with a 1.7x megahertz (MhZ) processor and in the early units, 4KB of RAM memory which was upped to 16KB later.
The tape drive was a standard monaural unit, similar to the audio cassette decks of the day. Sensitive to audio level changes, this early storage mechanism served the TRS-80 for quite a while until more data centric floppy disks were introduced. One drawback, however, is that the TRS-80 tended to create interference with electronics operating nearby. Using this alternate media required the owner of the unit to purchase an expansion interface, which cost a bit of money. The floppy drive system used was based on early technology by Western Digital corporation and allowed better storage and access to data. A TRS-80 user could also run disk based applications using the floppy drive.
The language of choice for the TRS-80 was BASIC — Beginners All-purpose Symbolic Instruction Code. A simple text based language that, in the first release allowed only level one decimal precision. BASIC later added floating point decimals and disk based I/O to the application.
Tandy sold the TRS-80 in its Radio Shack retail outlets and even offered a very 70's carrying case, or more accurately, cases. The computer did quite well for the retailer, selling 10,000 in the first month and around 50,000 by the end of its first year. There are probably a few die-hard hobbyists who still have the old Tandy TRS-80 and you might even be able to track one down on online shopping sites.