Comparison Logitech Wireless Combo MK240 vs Logitech Wireless Combo MK220

Traditional keyboards are divided into three main varieties — full-size, compact and ultra-compact. The main difference between them is that full-size models have a Num-block — an additional block with numeric keys and arithmetic signs. Compact models, respectively, do not have a num-block, and in ultra-compact models, the arrow block is either completely absent or located under the Enter key in the form of very small keys.

And full-size, and compact, and ultra-compact keyboards can have different types of layouts. At the same time, the arrangement of letters and numbers above the letters in all types of layouts is the same, the differences are in the shape and position of additional keys (special characters like backslash, system control, modifiers like Shift and Alt, etc.). Here are the most popular options:

— ANSI. The "American" layout format, the distinguishing features of which are, in particular, the same width of both Shift keys, the same labeling and assignment of the Alt keys, the single-row Enter key and the backslash located above it (which is often made slightly longer than the standard key).

— ISO. "European" layout format. The Enter key occupies two rows, while at the top it is slightly longer than at the bottom; the left Shift is shorter than the...right one, there is a backslash next to it; next to the bottom of the Enter may be a second backslash or other special character key; the right Alt is designated as Alt Gr and is intended for entering additional characters in European languages.

— K.S. The "Korean" keyboard layout provides a double-row Enter, as in the ISO described above, however, in this case, the lower part of the Enter is made longer, and not the upper one. The backslash is above Enter, next to Backspace, and Backspace itself is the same length as standard keys (that is, noticeably shorter than in other layouts).

— JIS. Keyboards with a "Japanese" layout have a double-row Enter with an increased length of the upper half — like the ISO described above. However, in this case, the backslash is not located on the left side of the keyboard, but on the right, next to Enter (where an additional symbol key can be located in ISO). Additional character keys may be provided — next to Backspace (as in KS) and/or to the left of the right Shift. In addition, the right Alt can be formatted as Alt Gr.

In addition to compact and full-size, there are also non-traditional keyboard formats:

— Num-block. Separately made block of numeric keys. With the help of such a device, you can, in particular, turn a compact keyboard into a full-size one. Among other things, this combination can be useful for travel: packing a Num-block separately from the keyboard is easier than finding a place for a full-sized "board". Another option for using the Num-block is to connect to a cash register, terminal, etc. to work as a calculator keyboard or in a similar capacity.

— Keypad. A specialized device in the form of a small (approximately 15 – 20 keys) keyboard under one hand; usually, it is complemented by an arm rest, and often also by side buttons for the thumb. Such devices are especially convenient for games and are mainly used in them — certain game actions can be attached to the keypad buttons (including those that are usually implemented through the menu or a key combination on a standard keyboard). The keypad can both complement the main keyboard and serve as a completely separate game pad.

— Non-standard. Non-standard format keyboards that do not belong to any of the varieties described above. The specific design and use of such devices may vary. So, these can be game models in the form of the left half of a standard keyboard (this part is mainly used in games); ultra-compact models for tablets (see "In the direction"); keyboards for TVs, supplemented with special buttons and designed to be held in two hands in the manner of a gamepad, etc.

The colour of the Cyrillic letters printed on the keyboard.

This colour is usually chosen so that the letters are clearly visible. This point does not affect the functionality of the keyboard, and the choice in this case depends mainly on personal preferences. However, there is also a practical point: for inexperienced users who have not mastered touch typing, it is desirable that the letters stand out as much as possible against the background of the keys.

Transparent letters are a separate case — they are used in keyboards equipped with a backlight (see below), due to which such characters, when the backlight is on, are visible even in the dark.

The operating time in this case is quite approximate: it is indicated for a certain average mode of use. The actual battery life may turn out to be either less or more than the claimed one, depending on the specifics of the application; in addition, the quality of a particular brand of batteries greatly affects the operating time. Nevertheless, this is a fairly reliable indicator, it is quite possible to evaluate different models and compare them with each other: the difference in the claimed operating time is usually quite consistent with the difference in real battery life when using batteries of similar quality.

It is worth saying that modern battery-powered keyboards have pretty solid battery life, measured in months; in the most "long-playing" models, the operating time is about 36 months (that is, 3 years).

The type of power used in the wireless mice that are included with some keyboards. It can be a replaceable battery or its own built-in battery.

Batteries or accumulators of AA (finger-type) or AAA (mini-fingerprint) format can be used as replaceable batteries. The main advantage of this power supply is the ability to quickly replace dead batteries with new ones - if there are any left, a few seconds are enough, and the mouse is ready to work again. However, batteries are often not included and must be purchased separately. In addition, anyway, you have to buy new batteries as the old ones wear out - or fork out for rather expensive batteries and, possibly, a charger.

Built-in battery, in turn, relieves the user of the need to purchase batteries. On the other hand, in the event of a discharge, such a battery cannot be quickly replaced, and the only option to continue working is to charge it, which can take quite a long time.