Urgent questions of modern Ukrainian orthography is complicated cases of the use of endings -а (-я) and -у (-ю) of terms in the genitive case second declension masculine with zero ending. Essence of the problem primarily lies in difficulty, some complexity, blurred of rules that motivate the use of a certain ending. According to the current Ukrainian spelling , in which numerous exceptions to the rule are illustrated by several examples mostly without comments, it is sometimes difficult to determine ending in a particular case. This is due to as extra linguistic intervention in the system of Ukrainian terminology in our times: the compilers of dictionaries use Russian language as a mediator, ignoring the morphological features of Ukrainian standards.
The aim of the article is to consider the complicated cases of the use of endings -а (-я) and -у (-ю) in some computer terminology units in the genitive case second declension masculine, as the process of normalization of endings -а (-я) and -у (-ю) in the Ukrainian computer terminology lasts until now.
The relevance of the research is in the necessity of normalization and making constant difficult cases of the use of computer terms the in the genitive case of second declension masculine singular, taking into consideration the rules of the Ukrainian language.
Well-known linguists as O. Sinyavskiy, S. Smal-Stocki, V. Yunosova, M. Zubkov, I. Yushchuk, O. Ponomariv, N. Lozova  and others examined the problem of consumption and normalization of endings in genitive case Second Declension Masculine.
Their studies reveal that during the development of the Ukrainian language the relation between endings of genitive singular masculine nouns has been changing. Ancient records [7, p. 19–22] show that the ending -а (-я) prevailed. Since the end of the fifteenth century ending -у (-ю) begins to displace ending -а (-я). At the end of the twentieth century there was an urgent need to normalize this grammatical category.
In the modern Ukrainian spelling there is a general tendency: nouns that are the names of certain subjects have the inflection -а (-я), nouns, that mean collectiveness or process or abstract concepts have the inflection -у (-ю), following this tendency, computer terms are divided into the following groups:
terms with the ending -а(-я) in the genitive case singular second declension
● names of people, titles, posts, personified objects and phenomena:
адміністратор (-а), інженер(а)-системотехнік (-а), користувач (-а),
оператор (-а), Паскаль (-я), програміст (-а), тестер (-а), хакер (-а);
● names of clearly defined subjects:
веб-вузол (-вузла), відеодисплейний (-ого) термінал (-а), дисплей (-я), екран (-а), комп’ютер (-а), кошик (-а), курсор (-а), лазерний (-ого) диск (-а), лазерний (-ого) принтер (-а), логін (-а), маркер (-а), модем (-а), накопичувач (-а), процесор (-а), роутер (-а), сервер (-а), сканер (-а), стовпець(-пця), шаблон (-а) (device, drawing);
● names of machines and their details: адаптер (-а), банер (-а), індикатор (-а), комутатор (-а), транслятор (-а), цифровий (-ого) перетворювач(-а);
● names of measurement units:
біт (-а), бод (-а), гігабайт (-а), кілобайт (-а) кілобіт (-а), мегабайт (-а), мегабіт (-а), піксель (-я), терабайт (-а),флоп (-а);
● names of foreign origin denoting elements of the structure of something, concrete objects, symbols, signs, geometric shapes and their parts, programs:
акронім (-а), архіватор (-а), асемблер (-а), Бейсик (-а), браузер (-а), буфер (-а), кластер (-а), програмний (-ого) модуль (-я);
terms with ending-у(-ю) in the genitive case singular second declension
● names for denoting the collective concepts:
вигляд (-у), вірус (-у),домен (-у), друк (-у), запам’ятовувальний (-ого) пристрій (-ю), імпульсний (-ого)код (-у), інформаційний ресурс (-у), код (-у), об’єктний (-ого) пул (-у), сайт (-у), символ (-у), статус (-у), текст (-у), трек (-у), формат (-у), функціонал (-у), шрифт (-у);
● terms of foreign origin, that mean the technical processe, part of the space, etc.: алгоритм (-у), апгрейд (-у), апдейт (-у), копірайтинг (-у), монтаж (-у);
● names of actions, properties, conditions, classes, features, events, abstract concepts:
діапазон (-у), зв’язок (-у), клас (-у), метод (-у), сервіс (-у), шаблон (-у)(зразок), штучний (-ого) інтелект (-у);
● most difficult with no suffix words and prefixal nouns (except names of creatures): ввід (-у), вивід (-у), запит (-у), запуск (-у), звіт (-у), Інтернет (-у), інтерфейс (-у), кеш (-у), програмний (-ого) інтерфейс (-у), розрив (-у), трекбол (-у), тренінговий (-ого)центр (-у);
Taking terminilogical unit macros as an example and making component analysis, we define what inflection to choose -а (-я) or -у (-ю).
Let us consider different meanings of terminological unit macros:
"Dictionary of foreign words : interpretation, derivation and usage" [8 ].
Macros – inform. 1. Means to replace one system by symbols of another system. 2. Sequence of commands that run at the touch of keys on the keyboard or a button on the screen.
Wikipedia treats the lexeme macro as follows: "in programming macro is called the abstraction, when all cases of text occurrence in the document corresponds to the template and are modified according to the rules. Also the name "macro" can be used in many other contexts, such as keyboard macros and language macro and so on. Most of these contexts is directly related to the same concept - one brief command or action during the execution unfolds in a a large number of instructions of lower level of abstraction".
Macros – a some sequence of actions user of applied program written in the form of separate procedure that can be performed automatically as a team.Workshop on Programming in VBA .
Macros – preserving the sequence of commands or keystrokes for future use. 
Macros – 1) Macros (from the Greek macros – large, long) sequence of commands and (or) keystrokesthat records makroregistrator under a unique name; 2) macrodefinition, block of commands associated with a specific unique name ("English-Ukrainian dictionary of computer technology, the Internet, programming") 
Analyzing the lexical meaning of terminological unitod macros we can conclude about the meaning:
the foreign origin term, that means a process, a sequence of actions, commands, abstraction – therefore forming the genitive singular, we should use the inflection -у.
talking about the morphemic structure, in the literature on programming and information technology terminological unit macros is used as a synonym for the word macrocomand. So, in the Ukrainian language terminological unit macros was formed as a result of truncation of the composite macrocomand:
macrocomand → macros → macros.
Since most with no suffix nouns Second Declension Masculine have the genitive singular ending -у (except for the names of creatures), then it is logical to use ending -у to form genitive case singular of terminological unit macros.
But in a computer discourse we face with oanoher definition for macros, such as "macros is called one of the means of communication or image with the inscription or not that boasts the ability to reflect accurately certain emotions. Often the image is reinforced by the statement or comment "(Wikipedia). 
Macros – image used to illustrate the expression of emotions, adding to the posts or comments during the communication in the network .
Macros - funny images attached to messages on the network and is intended to illustrate the transmission of emotional stress or personal attitude. In a broad sense any content that performs a similar function .
Analyzing such terms, we can conclude that these concepts have a common seme 'image', 'picture', therefore, it is clearly defined object, then according to the rules of Ukrainian spelling, you should use in the following meaning in the genitive case Second Declension singular ending -а.
As it was already stated: for Ukrainian language characteristic feature of the genitive declension singular has variability of form, that is caused by the lexical meaning of the word, its morphemic structure and emphasis. And it does not undermine linguistic norms, despite efforts of representatives of the exact sciences to achieve full certainty in sectoral terminological systems. On the one hand, the variability shows flexibility, wealth of lingual expressive means, makes it possible to differentiate the importance of computer terms and to recognize their shades, on the other hand it shows the unfinished process of standardization and continuity of Ukrainian computer terminology.
Thus, on the basis of the proposed study we can conclude:
• Depending on the meaning of the word we observe language tendency to consolidate semantic nuances by certain grammatical forms: 1) ending-а(-я) in computer terminology usually have terms that mean the job titles, occupations, names of well-defined objects, names of vehicles and their details, names of units of measure, names of foreign origin to describe elements of the structure of something, symbols, signs, programs ; 2) the ending -у (-ю) have terms that mean the total and composite concepts, foreign terms for technical processes;names of abstract concepts, actions, properties, conditions, features and so on.
• For the last time we observe expansion of semantics of some nouns, including terms, that leads to variability of endings in genitive case second declension singular.
For the last time seeing some nouns extension semantics, including timing, which leads to variability endings genitive singular second turning. Such lexical-semantic phenomenon also applies to computer terms and requires further investigation.